JP2017011135A - Electric field recording magnetic memory - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic memory capable of reducing more power consumption than the conventionally proposed race track memories.SOLUTION: An electric field recording magnetic memory comprises: a recording medium including a first ferromagnetic conductive layer and a ferromagnetic ferroelectric layer; a pair of electrodes for writing which applies an electric field to the ferromagnetic ferroelectric layer; a pair of electrodes for bit movement arranged in contact with the first ferromagnetic conductive layer; a non-magnetic layer arranged adjacent to a part of a surface of the first ferromagnetic conductive layer; a second ferromagnetic conductive layer arranged on a surface of the non-magnetic layer; a writing circuit which records magnetic information in the first ferromagnetic conductive layer by applying an electric field to the ferromagnetic ferroelectric layer via the pair of electrodes for writing; a bit moving circuit which moves a magnetic wall by passing current through the first ferromagnetic conductive layer via the pair of electrodes for bit movement; and a reading circuit which obtains a signal corresponding to the electric resistance between the first ferromagnetic conductive layer and the second ferromagnetic conductive layer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric field recording type magnetic memory.

  Hard disk drives (HDDs), which are large-capacity magnetic storage devices, have been improved in recording density. However, the increase in the amount of information to be recorded in recent years is far more rapid than the improvement in the recording density of HDDs. The improvement in HDD recording density is due to the “trilemma” that it is difficult to satisfy (1) ease of recording, (2) stable maintenance of recorded information, and (3) low error rate reading simultaneously. It is getting to the peak.

  As a technology capable of further increasing the capacity beyond conventional HDDs, recently, magnetic nanowires are used as recording media, and domain wall motion phenomenon caused by spin injection, and tunnel magnetoresistance effect (TMR effect) or giant magnetoresistance. A magnetic storage device using the effect (GMR effect) has been proposed (Patent Document 1). Such a magnetic storage device is called a “race track memory”. According to the racetrack memory, it is considered that three-dimensional information recording can be performed by forming the magnetic nanowire into a folded shape. Also, according to the racetrack memory, the recording bit in the magnetic nanowire is moved using the domain wall movement phenomenon caused by spin injection, so that the motor that is essential for the conventional HDD becomes unnecessary. The ability to omit the motor means that the power consumption of the apparatus can be greatly reduced.

US Pat. No. 6,834,005 JP 2010-176784 A International Publication 2010/032574 Pamphlet JP 2004-179219 A

  However, in the conventionally proposed racetrack memory, a magnetic field generated by an electric current (current magnetic field) is used to write information to the magnetic nanowire, as in a conventional HDD. Magnetic recording using a current magnetic field has a large energy loss, which hinders reduction in power consumption of the apparatus.

  An object of the present invention is to provide a magnetic memory capable of further reducing power consumption as compared with a conventionally proposed racetrack memory.

The magnetic memory of the present invention includes the following forms [1] to [10].
[1]
A recording medium comprising a first ferromagnetic conductive layer extending one-dimensionally, and a ferromagnetic ferroelectric layer stacked on at least a part of one surface of the first ferromagnetic conductive layer;
A pair of write electrodes for applying an electric field to the ferromagnetic ferroelectric layer;
A pair of bit moving electrodes disposed in contact with the first ferromagnetic conductive layer and spaced apart in the longitudinal direction of the recording medium;
A nonmagnetic layer disposed adjacent to a portion of the surface of the first ferromagnetic conductive layer;
A second ferromagnetic conductive layer disposed on the surface of the nonmagnetic layer and facing the first ferromagnetic conductive layer across the nonmagnetic layer;
By applying an electric field to the ferromagnetic ferroelectric layer through a pair of write electrodes, magnetization in a direction determined corresponding to the direction of the electric field is generated in the ferromagnetic ferroelectric layer, and the ferromagnetic ferroelectric layer A write circuit for recording magnetic information in the first ferromagnetic conductive layer by magnetization generated in
A bit moving circuit for moving a domain wall in the first ferromagnetic conductive layer by passing a current through the first ferromagnetic conductive layer via a pair of bit moving electrodes;
An electric field recording type magnetic memory comprising: a reading circuit that obtains a signal corresponding to an electric resistance between the first ferromagnetic conductive layer and the second ferromagnetic conductive layer.

In the present invention, the first ferromagnetic conductive layer “extends one-dimensionally” means that the first ferromagnetic conductive layer extends in the length direction and the first ferromagnetic conductive layer. This means that the direction in which the angle extends may change as the viewpoint moves along the length direction. For example, the first ferromagnetic conductive layer may extend linearly, may extend in a curved shape, or may have a three-dimensionally folded shape.
In the present invention, one electrode of the “one pair of write electrodes” may be the same as one electrode of the “one pair of bit moving electrodes”.

[2]
The first ferromagnetic conductive layer is one or a combination of two or more selected from the group consisting of an L2 ₁ type ferromagnetic alloy layer, an L1 ₀ type ferromagnetic alloy layer, and a D0 ₃ type ferromagnetic alloy layer, [1 ] The electric field recording type magnetic memory according to [1]

As used herein, "L2 ₁ type ferromagnetic alloy" means a ferromagnetic alloy having a L2 ₁ ordered structure, the "L1 ₀ type ferromagnetic alloy" ferromagnetic having an L1 ₀ ordered structure The term “D0 ₃ type ferromagnetic alloy” means a ferromagnetic alloy having a D0 ₃ type ordered structure.

[3]
The electric field recording magnetic memory according to [1] or [2], wherein the nonmagnetic layer is an insulating layer.

  In this specification, “insulating layer” means an electrical insulating layer.

[4]
A second ferromagnetic conductive layer, rutile-type conductive ferromagnetic oxide layer is one or more combinations selected from the group consisting of L1 ₀ type ferromagnetic alloy layer, and L2 ₁ type ferromagnetic alloy layer, The electric field recording type magnetic memory according to any one of [1] to [3].

[5]
A pinned magnetic conductive layer is disposed on the surface of the second ferromagnetic conductive layer,
The second ferromagnetic conductive layer is sandwiched between the pinned magnetic conductive layer and the nonmagnetic layer,
Fixed magnetic conductive layer, the antiferromagnetic conductive layer or L1 ₀ type ferromagnetic alloy layer, or a combination thereof, [1] field recording magnetic memory according to any one of - [4].

[6]
When the writing circuit records magnetic information in the first ferromagnetic conductive layer, the writing circuit further includes a heat assisting means for heating a region where the magnetic information is written in the first ferromagnetic conductive layer. [1] The electric field recording type magnetic memory according to any one of to [5].

[7]
The electric field recording according to any one of [1] to [6], wherein the pair of write electrodes are arranged so as to sandwich the ferromagnetic ferroelectric layer and the first ferromagnetic conductive layer in the stacking direction. Type magnetic memory.

[8]
First ferromagnetic conductive layer, a layer of L2 ₁ type ferromagnetic alloy represented by the following composition formula (1), a layer of L1 ₀ type ferromagnetic alloy represented by the following formula (2), and, below The electric field recording magnetic memory according to any one of [1] to [7], which is one or a combination of two or more selected from the group consisting of layers of a D0 type ₃ ferromagnetic alloy represented by the composition formula (3) .
X ₂ YZ (1)
(In formula (1), X is one or more elements selected from Fe, Co, and Ni; Y is one or more elements selected from Mn, Cr, V, and Ti; Z is Ge , One or more elements selected from Ga, Si, and Al.)
Mn ₅₀ Ge _x Ga _y Al _50-xy (2)
(In formula (2), x is a real number from 0 to 50; y is a real number from 0 to 50; x and y satisfy x + y ≦ 50.)
X ₃ Y (3)
(In formula (3), X is one or more elements selected from Mn and V; Y is one or more elements selected from Ge, Ga, Si, and Al.)

[9]
The electric field recording magnetic memory according to any one of [1] to [8], wherein the ferromagnetic ferroelectric layer includes a ferromagnetic ferroelectric material represented by the following composition formula (5).
_{(Bi 1-a X a)} (Fe 1-b M b) O 3 (5)
(In Formula (5), X is one or more elements selected from Ba and La; M is one or more elements selected from Mn and Ti; a and b are 0 ≦ a ≦ 0. 8 and a real number satisfying 0 ≦ b ≦ 0.5.)

[10]
A second ferromagnetic conductive layer, a layer of rutile-type conductive ferromagnetic oxide represented by the composition formula CrO _2, a layer of L1 ₀ type ferromagnetic alloy represented by the following formula (6), and the following composition The electric field recording magnetic memory according to any one of [1] to [9], which is one or a combination of two or more selected from the group consisting of L2 type ₁ ferromagnetic alloy layers represented by formula (7).
XY (6)
(In Formula (6), X is one or more elements selected from Fe and Co; Y is one or more elements selected from Pt, Pd, and Ni.)
X ₂ YZ (7)
(In Formula (7), X is one or more elements selected from Fe, Co, and Ni; Y is one or more elements selected from Mn, Cr, V, and Ti; Z is Ge , One or more elements selected from Ga, Si, and Al.)

  According to the electric field recording type magnetic memory of the present invention, since information is written to the recording medium by an electric field without using a current magnetic field, the power consumption can be further reduced as compared with the conventionally proposed racetrack memory. .

It is a figure which illustrates typically the composition of the electric field recording type magnetic memory concerning one embodiment of the present invention. It is a figure which illustrates typically the structure of the electric field recording type magnetic memory which concerns on other one Embodiment of this invention. It is a figure which illustrates typically the structure of the electric field recording type magnetic memory which concerns on other one Embodiment of this invention. It is a figure which illustrates typically the structure of the electric field recording type magnetic memory which concerns on other one Embodiment of this invention. It is a figure which illustrates typically the structure of the electric field recording type magnetic memory which concerns on other one Embodiment of this invention. 5 is a graph showing an example of the relationship between saturation magnetization M _s and temperature T in the first ferromagnetic conductive layer 11 and the ferromagnetic ferroelectric layer 12.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings do not necessarily reflect exact dimensions. In the drawing, some symbols may be omitted. In the present specification, “A to B” for the numerical values A and B means “A or more and B or less” unless otherwise specified. In the notation, when the unit of the numerical value A is omitted, the unit attached to the numerical value B is applied as the unit of the numerical value A. In addition, the form shown below is an illustration of this invention and this invention is not limited to these forms.

<Electric field recording type magnetic memory (1)>
FIG. 1 is a diagram schematically illustrating a configuration of an electric field recording magnetic memory 100 according to an embodiment of the present invention. The electric field recording type magnetic memory 100 includes a first ferromagnetic conductive layer 11 extending one-dimensionally and a ferromagnetic ferroelectric layer 12 stacked on one surface of the first ferromagnetic conductive layer 11. A pair of write electrodes 21 and 22 for applying an electric field to the ferromagnetic ferroelectric layer 12; and in contact with the first ferromagnetic conductive layer 11 apart from each other in the longitudinal direction of the recording medium 10; A pair of bit transfer electrodes 31 and 32; a nonmagnetic layer 41 disposed adjacent to a part of the surface of the first ferromagnetic conductive layer 11; A second ferromagnetic conductive layer 42 disposed on the surface and facing the first ferromagnetic conductive layer 11 with the nonmagnetic layer 41 interposed therebetween; ferromagnetic ferroelectricity via a pair of write electrodes 21, 22 By applying an electric field to the layer 12, the magnetization M ₀ in a direction determined corresponding to the direction of the electric field is changed to ferromagnetic strength. A write circuit 50 for recording the magnetic information of M _{1 on} the first ferromagnetic conductive layer 11 by the magnetization M ₀ generated in the dielectric layer 12 and the magnetization M ₀ generated in the ferromagnetic ferroelectric layer 12; A bit moving circuit 60 that moves the domain walls 13, 13,... In the first ferromagnetic conductive layer 11 by passing a current through the first ferromagnetic conductive layer 11 through 31, 32; A reading circuit 70 is provided for obtaining a signal corresponding to the electric resistance between the ferromagnetic conductive layer 11 and the second ferromagnetic conductive layer 42. In the electric field recording magnetic memory 100, the pair of write electrodes 21 and 22 sandwich the ferromagnetic ferroelectric layer 12 and the first ferromagnetic conductive layer 11 in the stacking direction (up and down direction in the drawing of FIG. 1). Is arranged.

  In FIG. 1, a first ferromagnetic conductive layer 11, a ferromagnetic ferroelectric layer 12, write electrodes 21 and 22, bit moving electrodes 31 and 32, a nonmagnetic layer 41, and a second ferromagnetic conductive layer 42. Are shown in a cross-sectional view, and the writing circuit 50, the bit moving circuit 60, and the reading circuit 70 are shown in a block diagram. The horizontal direction in FIG. 1 is the extending direction (longitudinal direction) of the first ferromagnetic conductive layer 11. The vertical direction in FIG. 1 is the first ferromagnetic conductive layer 11, the ferromagnetic ferroelectric layer 12, the writing electrodes 21, 22, the bit moving electrodes 31, 32, the nonmagnetic layer 41, and the second ferromagnetic layer. This is the thickness direction of the conductive layer 42. 1 are the first ferromagnetic conductive layer 11, the ferromagnetic ferroelectric layer 12, the write electrodes 21 and 22, the bit moving electrodes 31 and 32, the nonmagnetic layer 41, and the second This is the width direction of the ferromagnetic conductive layer 42.

(First ferromagnetic conductive layer 11)
The first ferromagnetic conductive layer 11 is a ferromagnetic layer having conductivity, and is a layer in which magnetic information is recorded. The first ferromagnetic conductive layer 11 has perpendicular magnetic anisotropy, and magnetic information is expressed as magnetization in a direction perpendicular to the surface of the first ferromagnetic conductive layer 11, that is, magnetization in the vertical direction on the paper surface of FIG. To be recorded. .. Are formed at positions where the magnetization direction of the first ferromagnetic conductive layer 11 changes. As described later, by controlling the current that the bit moving circuit 60 passes through the first ferromagnetic conductive layer 11, the domain walls 13, 13,... Can be moved by a desired distance. In the electric field recording magnetic memory 100, moving the domain walls 13, 13,... In the first ferromagnetic conductive layer 11 is equivalent to moving the recording bits in the first ferromagnetic conductive layer 11. .

In order to realize high-speed writing and reading, it is preferable that the moving speed of the domain walls 13, 13,... In the first ferromagnetic conductive layer 11 is high. The moving speed of the domain wall in the ferromagnetic conductive material is proportional to the spin polarizability P of the material and inversely proportional to the saturation magnetization M _s and the magnetic saturation constant α. Therefore, it is preferable to use a material having a small saturation magnetization M _s and a magnetic saturation constant α and a large spin polarizability P for the first ferromagnetic conductive layer 11.
Further, the magnetic information recorded in the first ferromagnetic conductive layer 11 is converted into a tunnel magnetoresistive effect (TMR effect) or giant magnetism between the first ferromagnetic conductive layer 11 and the second ferromagnetic conductive layer 42. In reading using the resistance effect (GMR effect), in order to reduce read errors, it is preferable that the tunnel magnetoresistance ratio (TMR ratio) or the giant magnetoresistance effect (GMR effect) is large. The TMR ratio or GMR between the first ferromagnetic conductive layer 11 and the second ferromagnetic conductive layer 42 increases as the spin polarizability of the first ferromagnetic conductive layer 11 and the second ferromagnetic conductive layer 42 increases. The ratio is large. Therefore, also from this point, it is preferable to use a material having a high spin polarizability P for the first ferromagnetic conductive layer 11.
From these viewpoints, a first ferromagnetic conductive layer 11, L2 ₁ type ferromagnetic alloy layer, L1 ₀ type ferromagnetic alloy layer, and one or more selected from the group consisting of D0 ₃ type ferromagnetic alloy layer A combination is preferred. More specifically, a first ferromagnetic conductive layer 11 is a layer of L2 ₁ type ferromagnetic alloy represented by the following composition formula (1), L1 ₀ type ferromagnetic represented by the following formula (2) It is preferably a combination of one or two or more selected from the group consisting of an alloy layer and a layer of a D0 type ₃ ferromagnetic alloy represented by the following composition formula (3).
X ₂ YZ (1)
(In formula (1), X is one or more elements selected from Fe, Co, and Ni; Y is one or more elements selected from Mn, Cr, V, and Ti; Z is Ge , One or more elements selected from Ga, Si, and Al.)
Mn ₅₀ Ge _x Ga _y Al _50-xy (2)
(In formula (2), x is a real number from 0 to 50; y is a real number from 0 to 50; x and y satisfy x + y ≦ 50.)
X ₃ Y (3)
(In formula (3), X is one or more elements selected from Mn and V; Y is one or more elements selected from Ge, Ga, Si, and Al.)
From the viewpoint of increasing the spin polarizability P of the first ferromagnetic conductive layer 11, it is more preferable that the first ferromagnetic conductive layer 11 includes an L2 type ₁ ferromagnetic alloy layer, and more specifically, It is preferable to include a layer of L2 type ₁ ferromagnetic alloy represented by the composition formula (1).

  The thickness of the first ferromagnetic conductive layer 11 is not particularly limited, but is preferably 1 to 200 nm, and more preferably 5 to 50 nm.

(Ferromagnetic ferroelectric layer 12)
The ferromagnetic ferroelectric layer 12 is a layer of a ferromagnetic ferroelectric material having a property that polarization is induced by an external electric field and magnetization is induced by polarization. When an electric field is applied to the ferromagnetic ferroelectric layer 12 through the pair of write electrodes 21 and 22, the ferromagnetic ferroelectric layer 12 has polarization along the electric field (open arrow P _{0 in} FIG. 1). At the same time, magnetization in the direction determined in accordance with the direction of the electric field (arrow M _{0 in} FIG. 1) is induced. Since the first ferromagnetic conductive layer 11 is magnetically coupled to the ferromagnetic ferroelectric layer 12, the magnetization M ₀ generated in the ferromagnetic ferroelectric layer 12 causes a magnetization M in a direction corresponding to the magnetization M _{0. 1} is recorded as magnetic information in the first ferromagnetic conductive layer 11.

For the ferromagnetic ferroelectric layer 12, for example, a ferromagnetic ferroelectric material represented by the following general formula (4) can be adopted.
_{(A x B 1-x)} l (M y N 1-y) m O n (4)
(In the formula (4), A and B each independently represent Bi, La, Tb, Pb, Y, Cr, Co, Ba, Lu, Yb or Eu; and M and N each independently, Represents Fe, Mn, Ni, Ti, Cr, Co or V; x represents a real number of 0 to 1; y represents a real number of 0 to 1; l represents an integer of 1 to 3; 3 represents an integer of 3; n represents an integer of 3 to 6)
Examples of known ferromagnetic ferroelectric materials represented by the general formula (4) include BiMnO ₃ , TbMnO ₃ , TbMn ₂ O ₅ , YMnO ₃ , EuTiO ₃ , CoCr ₂ O ₄ , Cr ₂ O ₃ , BiMn _{0. .5 Ni 0.5 O 3, BiFe 0.5} Cr 0.5 O 3, La 0.1 Bi 0.9 MnO 3, La 1-x Bi x Ni 0.5 Mn 0.5 O 3, Bi 1 _-x Ba _x FeO _3, and the like can be given.

The ferromagnetic ferroelectric layer 12 preferably contains a ferromagnetic ferroelectric material represented by the following composition formula (5).
_{(Bi 1-a X a)} (Fe 1-b M b) O 3 (5)
(In Formula (5), X is one or more elements selected from Ba and La; M is one or more elements selected from Mn and Ti; a and b are 0 ≦ a ≦ 0. 8 and a real number satisfying 0 ≦ b ≦ 0.5.)
In the formula (5), a and b preferably satisfy 0 <a ≦ 0.8 and 0 <b ≦ 0.5, 0 <a ≦ 0.8, 0 <b ≦ 0.5, and More preferably, 0.01 ≦ a + b ≦ 1.3 is satisfied.
By replacing a part of Bi in BiFeO ₃ known as a dielectric material with the predetermined element X and a part of Fe with the predetermined element M, preferable ferromagnetism and dielectric properties are exhibited. At this time, when the substitution ratios a and b are within the above ranges, ferromagnetic and ferroelectric properties particularly suitable for the operation of the electric field recording magnetic memory 100 are manifested simultaneously.
Examples of such materials include Bi (FeMn) O-based materials, (BiBa) FeO-based materials, (BiBaLa) (FeMn) O-based materials, (BiBaLa) (FeMnTi) O-based materials, and (BiLa). ) FeO-based materials. More specifically, Bi (Fe _0.95 Mn _0.05 ) O ₃ , (Bi _0.8 Ba _0.2 ) FeO ₃ , (Bi _0.5 Ba _0.3 La _0.2 ) FeO ₃ , (Bi _0.7 La _0.3 ) (Fe _0.7 Mn _0.3 ) O ₃ , (Bi _0.5 Ba _0.3 La _0.2 ) (Fe _0.7 Mn _0.1 Ti _0.2 ) O _{3 and the} like.

The thickness of the ferromagnetic ferroelectric layer 12 is not particularly limited, but is preferably 5 to 200 nm, and more preferably 10 to 50 nm. From the viewpoint of generating a stronger electric field between the pair of write electrodes 21 and 22 when the write circuit 50 applies a voltage to the pair of write electrodes 21 and 22, the write circuit 50 is preferably 200 nm or less, and preferably 50 nm or less. More preferably. Also, in that it can increase the magnetization M ₁ to be written into the first ferromagnetic conductive layer 11, it is preferably 5nm or more, and more preferably 10nm or more.

(Nonmagnetic layer 41)
The nonmagnetic layer 41 is a paramagnetic or diamagnetic layer. From the viewpoint of increasing the magnetoresistance change rate, the nonmagnetic layer 41 is preferably an electrically insulating layer. The material constituting the non-magnetic layer 41, for _{example, MgO, Al 2 O 3,} SiO 2, TiO 2, AlN, Si 3 N 4, Cr 2 O 3 and the like preferably. A conductive material such as Cu, Ag, or Cr may be used.

  The thickness of the nonmagnetic layer 41 is preferably 0.5 to 5 nm, and more preferably 1 to 3 nm. From the viewpoint of developing the tunnel magnetoresistive effect, the thickness of the nonmagnetic layer 41 is preferably 5 nm or less, and more preferably 3 nm or less. Further, from the viewpoint of ease of production, the thickness is preferably 0.5 nm or more, and more preferably 1 nm or more.

(Second ferromagnetic conductive layer 42)
The second ferromagnetic conductive layer 42 is a ferromagnetic conductive layer having a fixed magnetization (arrow M _{2 in} FIG. 1), and the first ferromagnetic conductive layer 11 and the ferromagnetic of the tunnel or giant magnetoresistive element. An electrode pair is configured. The second ferromagnetic conductive layer 42 acts as a pinned magnetic layer in the tunnel or giant magnetoresistive element. The magnetization of the second ferromagnetic conductive layer 42 has a component parallel or antiparallel to the direction of magnetization recorded in the first ferromagnetic conductive layer 11.

As a material constituting the second ferromagnetic conductive layer 42, a material having a large spin polarizability P is preferable from the viewpoint of increasing the magnetoresistance change rate. From the viewpoint of preventing magnetization reversal, a material having high magnetic anisotropy is preferable. From this point of view, the second ferromagnetic conductive layer 42, the rutile type conductive ferromagnetic oxide layer, L1 ₀ type ferromagnetic alloy layer, and one or selected from the group consisting of L2 ₁ type ferromagnetic alloy layer preferably 2 or more combinations, and more specifically, a layer of rutile-type conductive ferromagnetic oxide represented by the composition formula CrO _2, L1 ₀ type ferromagnetic represented by the following formula (6) One or more combinations selected from the group consisting of an alloy layer and an L2 type ₁ ferromagnetic alloy layer represented by the following composition formula (7) are preferable.
XY (6)
(In Formula (6), X is one or more elements selected from Fe and Co; Y is one or more elements selected from Pt, Pd, and Ni.)
X ₂ YZ (7)
(In Formula (7), X is one or more elements selected from Fe, Co, and Ni; Y is one or more elements selected from Mn, Cr, V, and Ti; Z is Ge , One or more elements selected from Ga, Si, and Al.)
Among these, the rutile-type conductive ferromagnetic oxide layer represented by the composition formula CrO ₂ is used as the _second layer because the spin polarizability and the magnetic anisotropy can be simultaneously increased in one layer. The ferromagnetic conductive layer 42 can be particularly preferably employed.

  The thickness of the second ferromagnetic conductive layer 42 is not particularly limited, but is preferably 1 to 200 nm, and more preferably 5 to 50 nm.

(Writing electrodes 21 and 22, bit moving electrodes 31 and 32)
As a material constituting the pair of write electrodes 21 and 22 and the pair of bit moving electrodes 31 and 32, a known conductive material can be used as an electrode material without any particular limitation. However, a nonmagnetic conductive material is preferable.

(Write circuit 50)
The write circuit 50 is connected to the pair of write electrodes 21 and 22 and applies an electric field to the ferromagnetic ferroelectric layer 12 through the pair of write electrodes 21 and 22. Magnetization occurs in the ferromagnetic ferroelectric layer 12 in a direction (corresponding to the electric field in FIG. 1) determined in accordance with the direction of the applied electric field. Magnetic information is recorded in the first ferromagnetic conductive layer 11 by the magnetization generated in the ferromagnetic ferroelectric layer 12. The direction of magnetization generated in the ferromagnetic ferroelectric layer 12 is determined by the polarity of the electric field applied to the ferromagnetic ferroelectric layer 12. The write circuit 50 controls the polarity of the potential difference applied to the pair of write electrodes 21 and 22 so that the magnetization in a desired direction is recorded in the first ferromagnetic conductive layer 11.

(Bit moving circuit 60)
The bit moving circuit 60 is connected to a pair of bit moving electrodes 31 and 32. The bit transfer circuit 60 causes a current to flow through the first ferromagnetic conductive layer 11 through the pair of bit transfer electrodes 31 and 32, thereby causing domain walls in the first ferromagnetic conductive layer 11 by spin injection magnetization reversal. 13, 13, ... are moved. The current that the bit transfer circuit 60 passes through the first ferromagnetic conductive layer 11 is such that the current density in the first ferromagnetic conductive layer 11 is the critical current density at which spin injection magnetization reversal occurs in the first ferromagnetic conductive layer 11. It is controlled to exceed. The distance traveled by the domain walls 13, 13... Is proportional to the amount of charge that has flowed through the first ferromagnetic conductive layer 11. The bit moving circuit 60 charges to be injected into the first ferromagnetic conductive layer 11 so that the domain walls 13, 13,... In the first ferromagnetic conductive layer 11 move by a distance corresponding to the number of bits to be moved. The amount of control.

(Reading circuit 70)
The reading circuit 70 is a circuit that obtains a signal corresponding to the electrical resistance between the first ferromagnetic conductive layer 11 and the second ferromagnetic conductive layer 42. The read circuit 70 is connected to the second ferromagnetic conductive layer 42 and another electrode (here, the writing electrode 21) disposed in contact with the first ferromagnetic conductive layer 11. Due to the tunnel or giant magnetoresistance effect, the electrical resistance between the first ferromagnetic conductive layer 11 and the second ferromagnetic conductive layer 42 is the second ferromagnetic conductive layer of the first ferromagnetic conductive layer 11. 42 changes depending on the relationship between the direction of the magnetization M _r of the magnetic domain which face each other through the nonmagnetic layer 41, the magnetization M ₂ of the orientation of the second ferromagnetic conductive layer 42. That is, a first ferromagnetic conductive layer 11 electrical resistance between the second ferromagnetic conductive layer 42 becomes minimal when the magnetization M _r and magnetization M ₂ are parallel, the magnetization, M _r magnetization M Maximum when antiparallel to ₂ . Since the magnetization M ₂ of the second ferromagnetic conductive layer 42 necessarily has a component parallel or antiparallel to the magnetization recorded in the first ferromagnetic conductive layer 11, the first ferromagnetic conductive layer 11. When the electrical resistance between the second ferromagnetic conductive layer 42 will vary depending on the direction of magnetization M _r. Therefore, by obtaining a signal corresponding to the electrical resistance between the first ferromagnetic conductive layer 11 and the second ferromagnetic conductive layer 42, the second ferromagnetic conductive layer of the first ferromagnetic conductive layer 11 is obtained. 42 can read the information recorded as the magnetization M _r in domains facing across the non-magnetic layer 41. In order for the reading circuit 70 to obtain a signal corresponding to the electrical resistance between the first ferromagnetic conductive layer 11 and the second ferromagnetic conductive layer 42, the second ferromagnetic conductive layer 42 and other electrodes (for writing) The current (sense current) that flows between the electrode 21) and the current density in the first ferromagnetic conductive layer 11 is less than the critical current density at which spin injection magnetization reversal occurs in the first ferromagnetic conductive layer 11. To be controlled.

<Electric field recording type magnetic memory (2)>
In the above description regarding the present invention, the electric field recording type magnetic memory 100 having the nonmagnetic layer 41 and the second ferromagnetic conductive layer 42 has been exemplified, but the present invention is not limited to this form. In addition to the nonmagnetic layer and the second ferromagnetic conductive layer, an electric field recording type magnetic memory having a fixed magnetic conductive layer disposed on the surface of the second ferromagnetic conductive layer may be provided. . FIG. 2 is a diagram schematically illustrating an electric field recording type magnetic memory 1100 according to another embodiment, and corresponds to FIG. 2, the same elements as those already shown in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and the description thereof is omitted.

(Pinned magnetic conductive layer 43)
The electric field recording type magnetic memory 1100 is different from the electric field recording type magnetic memory 100 in that it further includes a fixed magnetic conductive layer 43 in addition to the nonmagnetic layer 41 and the second ferromagnetic conductive layer 42. The pinned magnetic conductive layer 43 is disposed on the surface of the second ferromagnetic conductive layer 42 and faces the nonmagnetic layer 41 with the second ferromagnetic conductive layer 42 interposed therebetween. In the electric field recording magnetic memory 1100, the reading circuit 70 is connected to the fixed magnetic conductive layer 43 and another electrode (here, the writing electrode 21) disposed in contact with the first ferromagnetic conductive layer 11. ing.

Fixed magnetic conductive layer 43, the antiferromagnetic conductive layer or L1 ₀ type ferromagnetic alloy layer, or a combination thereof, and a second ferromagnetic conductive layer 42 and magnetically coupled to. Since the apparent magnetic anisotropy of the second ferromagnetic conductive layer 42 is enhanced by the pinned magnetic conductive layer 43, even when a material having a low magnetic anisotropy is used for the second ferromagnetic conductive layer 42. It becomes easy to suppress the magnetization reversal of the second ferromagnetic conductive layer 42. Therefore, in the electric field recording type magnetic memory 1100 having the fixed magnetic conductive layer 43, the second ferromagnetic conductive layer 42 is a material having a large spin polarizability but not so high magnetic anisotropy, for example, L2 type _1. A ferromagnetic alloy can be preferably used.

  As the antiferromagnetic conductive layer in the fixed magnetic conductive layer 43, a known antiferromagnetic alloy can be used without any particular limitation. As a preferable antiferromagnetic alloy in the fixed magnetic conductive layer 43, for example, a Mn-based alloy (for example, a Mn—Pt alloy, a Mn—Ir alloy, a Mn—Ni alloy, etc.) can be cited.

The L1 ₀ type ferromagnetic alloy layer in the fixed magnetic conductive layer 43, for example, the above composition formula can be preferably used an L1 ₀ type ferromagnetic alloy represented by (6), and more specifically, for example, a composition formula FePt can FePd, CoPt, CoPd, or are preferably used L1 ₀ type ferromagnetic alloy represented by FeNi.

  The thickness of the pinned magnetic conductive layer 43 is not particularly limited, but is preferably 1 to 200 nm, and more preferably 5 to 50 nm. From the viewpoint of making the magnetization inversion of the second ferromagnetic conductive layer difficult to occur, the thickness is preferably 1 nm or more, and more preferably 5 nm or more.

<Electric field recording type magnetic memory (3)>
In the above description of the present invention, the electric field recording type magnetic memories 100 and 1100 in which the ferromagnetic ferroelectric layer 12 is laminated on the entire one surface of the first ferromagnetic conductive layer 11 are exemplified. It is not limited to the said form. For example, an electric field recording type magnetic memory in which a ferromagnetic ferroelectric layer is laminated only on a part of one surface of the first ferromagnetic conductive layer may be used. In the above description of the present invention, the read circuit 70 is connected to the second ferromagnetic conductive layer 42 (or the fixed magnetic conductive layer 43) and the write electrode 21. Although 1100 is illustrated, the present invention is not limited to this form. For example, another electrode provided separately in contact with the first ferromagnetic conductive layer is separately provided, and a reading circuit is connected to the other electrode and the second ferromagnetic conductive layer (or the fixed magnetic conductive layer). The electric field recording type magnetic memory can be also used. FIG. 3 is a diagram schematically illustrating an electric field recording type magnetic memory 2100 according to another embodiment, and corresponds to FIG. In FIG. 3, the same elements as those already shown in FIGS. 1 and 2 are denoted by the same reference numerals as those in FIGS.

(Recording medium 2010: ferromagnetic ferroelectric layer 12 ′)
The electric field recording type magnetic memory 2100 has a recording medium 2010 instead of the recording medium 10. The recording medium 2010 is formed only on a part of one surface of the first ferromagnetic conductive layer 11 instead of the ferromagnetic ferroelectric layer 12 stacked on the entire one surface of the first ferromagnetic conductive layer 11. It differs from the recording medium 10 in that it has a laminated ferromagnetic ferroelectric layer 12 ′. The material constituting the ferromagnetic ferroelectric layer 12 ′ is the same as that of the ferromagnetic ferroelectric layer 12. In the electric field recording type magnetic memory 2100, the pair of write electrodes 21 and 22 sandwich the ferromagnetic ferroelectric layer 12 ′ and the first ferromagnetic conductive layer 11 in the stacking direction (up and down direction in FIG. 3). Are arranged as follows.

(Counter electrode 45 for reading)
In the electric field recording magnetic memory 2100, the reading circuit 70 is connected to the second ferromagnetic conductive layer 42 and the reading counter electrode 45. The reading counter electrode 45 is disposed in contact with the first ferromagnetic conductive layer 11 and faces the second ferromagnetic conductive layer 42 across the nonmagnetic layer 41 and the first ferromagnetic conductive layer 11. ing. As a material constituting the counter electrode 45 for reading, a known conductive material can be used as an electrode material without any particular limitation. However, a nonmagnetic conductive material is preferable.

  In the above description of the present invention, the ferromagnetic ferroelectric layer 12 ′ laminated only on a part of one surface of the first ferromagnetic conductive layer 11, the nonmagnetic layer 41 and the first ferromagnetic conductive layer 11 are formed. A reading counter electrode 45 disposed in contact with the first ferromagnetic conductive layer 11 so as to face the second ferromagnetic conductive layer 42, and the reading circuit 70 has a second ferromagnetic conductive layer. The electric field recording type magnetic memory 2100 connected to the layer 42 and the reading counter electrode 45 is exemplified, but the present invention is not limited to this form. For example, the first ferromagnetic conductive layer includes a ferromagnetic ferroelectric layer that is stacked only on a part of one surface, and the reading circuit, the writing circuit, and / or the bit moving circuit have one electrode (for example, the first ferromagnetic conductive layer). It is also possible to provide an electric field recording type magnetic memory that shares a writing electrode disposed in contact with one ferromagnetic conductive layer.

<Electric field recording type magnetic memory (4)>
In the above description of the present invention, when the magnetization to be written to the first ferromagnetic conductive layer 11 by the write circuit 50 is opposite to the magnetization already present in the area where writing is performed, the ferromagnetic ferroelectric layer is applied by the electric field. Although the electric field recording type magnetic memories 100, 1100, and 2100 in which the magnetization of the first ferromagnetic conductive layer 11 is reversed only by the magnetization induced by the magnetic field 12 are illustrated, the current recording magnetic memories 100, 1100, and 2100 are used as long as a current magnetic field is not used for writing magnetization. The invention is not limited to this form. For example, when the writing circuit records the magnetic information on the first ferromagnetic conductive layer, it further includes a heat assist means for heating a region of the first ferromagnetic conductive layer where the magnetic information is written. An electric field recording type magnetic memory can also be used. FIG. 4 is a diagram schematically illustrating an electric field recording type magnetic memory 3100 according to another embodiment, and corresponds to FIG. In FIG. 4, the same elements as those already shown in FIGS. 1 to 3 are denoted by the same reference numerals as those in FIGS.

(Thermal assist means 81)
The electric field recording type magnetic memory 3100 is different from the electric field recording type magnetic memory 100 in that the electric field recording type magnetic memory 3100 further includes a heat assist means 81 and has a writing electrode 21 ′ instead of the writing electrode 21. The heat assisting means 81 is connected to the writing circuit 50, and heats the region by irradiating the region where the writing of the first ferromagnetic conductive layer 11 is performed in synchronization with the writing operation. The writing electrode 21 ′ is different from the writing electrode 21 in that a through hole 21 ′ for passing the laser irradiated from the heat assist means 81 through the surface of the first ferromagnetic conductive layer 11 is provided. ing.

FIG. 6 is a graph showing an example of the relationship between the saturation magnetization M _s and the temperature T in the first ferromagnetic conductive layer 11 and the ferromagnetic ferroelectric layer 12. In the graph of FIG. 6, M _{S, 11} (T) represents the saturation magnetization of the first ferromagnetic conductive layer 11, and M _{S, 12} (T) represents the saturation magnetization of the ferromagnetic ferroelectric layer 12. Note the relationship between the coercive force H _C and the temperature T also shows the same tendency as the relationship between the saturation magnetization M _s and the temperature T shown in the graph of FIG. At the initial temperature T ₀ , M _{S, 11} (T ₀ )> M _{S, 12} (T ₀ ). When the first ferromagnetic conductive layer 11 is irradiated with laser from the heat assist means 81, the temperature of the first ferromagnetic conductive layer 11 rises to T ₁ (> T ₀ ), and the ferromagnetic ferroelectric layer 12 The temperature rises to T2 (> T ₀ ) due to heat transfer from the first ferromagnetic conductive layer 11. In any of the first ferromagnetic conductive layer 11 and the ferromagnetic ferroelectric layer 12, the saturation magnetization and the coercive force decrease as the temperature increases. However, since the thermal conductivity of the ferromagnetic ferroelectric layer 12 is lower than the thermal conductivity of the first ferromagnetic conductive layer 11, the temperature rise T ₂ -T ₀ in the ferromagnetic ferroelectric layer 12 is the first ferromagnetic conductive layer. 11 is sufficiently small with respect to the temperature rise T ₁ -T ₀ . As a result, M _{S, 11} (T ₁ ) <M _{S, 12} (T ₂ ), and the magnitude relationship between the saturation magnetization of the first ferromagnetic conductive layer 11 and the saturation magnetization of the ferromagnetic ferroelectric layer 12 is reversed. . As described above, when the saturation magnetization of the first ferromagnetic conductive layer 11 becomes smaller than the saturation magnetization of the ferromagnetic ferroelectric layer 12, the writing circuit 50 is strong via the pair of writing electrodes 21 'and 22. When an electric field is applied to the magnetic ferroelectric layer 12, the magnetization of the first ferromagnetic conductive layer 11 is easily reversed by the magnetization induced in the ferromagnetic ferroelectric layer 12. After the magnetization of the first ferromagnetic conductive layer 11 is reversed, when the laser irradiation from the heat assist means 81 is stopped, the temperatures of the first ferromagnetic conductive layer 11 and the ferromagnetic ferroelectric layer 12 are again changed to the initial temperatures. It drops to T _0, return to the saturation magnetization of the first ferromagnetic conductive layer 11 and the ferromagnetic and ferroelectric layer 12 also each _{M S,} 11 _{(T 0)} and _{M S, 12 (T 0)} .

  As described above, according to the electric field recording magnetic memory 3100 having the thermal assist means 81, the magnetization of the first ferromagnetic conductive layer 11 is reversed only by the magnetization induced in the ferromagnetic ferroelectric layer 12 by the electric field. Even if the coercive force of the first ferromagnetic conductive layer 11 is so high that the magnetic field is difficult, it is possible to reverse the magnetization of the first ferromagnetic conductive layer 11 without using a current magnetic field.

<Electric field recording type magnetic memory (5)>
In the above description regarding the present invention, the electric field recording type magnetic memory 3100 in which the heat assist means 81 irradiates the first ferromagnetic conductive layer 11 with laser from the first ferromagnetic conductive layer 11 side of the recording medium 10 is exemplified. However, the present invention is not limited to this form. For example, an electric field recording type magnetic memory in which the heat assist means 81 irradiates the first ferromagnetic conductive layer 11 with laser from the ferromagnetic ferroelectric layer 12 side of the recording medium 10 can be used. FIG. 5 is a diagram schematically illustrating an electric field recording type magnetic memory 4100 according to another embodiment, and corresponds to FIG. In FIG. 5, the same elements as those already shown in FIGS. 1 to 4 are denoted by the same reference numerals as those in FIGS.

  The electric field recording type magnetic memory 4100 has a writing electrode 21 in place of the writing electrode 21 ′, has a writing electrode 22 ′ in place of the writing electrode 22, and the heat assist means 81 has a strength of the recording medium 10. It differs from the electric field recording magnetic memory 3100 in that it is provided so as to irradiate a laser from the magnetic ferroelectric layer 12 side. The writing electrode 22 ′ is different from the writing electrode 22 in that a through hole 22 ′ for passing the laser irradiated from the heat assist means 81 through the surface of the ferromagnetic ferroelectric layer 12 is provided. .

  In the electric field recording magnetic memory 4100, the ferromagnetic ferroelectric layer 12 is made of a ferromagnetic ferroelectric material that transmits a laser emitted from the thermal assist means 81. The laser irradiated from the heat assist means 81 enters the ferromagnetic ferroelectric layer 12 through the through-hole 22′a provided in the writing electrode 22 ′, and then passes through the ferromagnetic ferroelectric layer 12 and passes through the ferromagnetic ferroelectric layer 12. 1 is incident on one ferromagnetic conductive layer 11. At this time, most of the energy of the laser is converted into heat in the first ferromagnetic conductive layer 11. Since the thermal conductivity of the ferromagnetic ferroelectric layer 12 is lower than the thermal conductivity of the first ferromagnetic conductive layer 11, the temperature rise of the ferromagnetic ferroelectric layer 12 during the laser irradiation increases the first ferromagnetic conductive layer 11. It can be kept low enough against the temperature rise. Therefore, even with such an electric field recording type magnetic memory 4100, the first ferromagnetic conductive layer depends only on the magnetization induced in the ferromagnetic ferroelectric layer 12 by the electric field, as in the electric field recording type magnetic memory 3100 described above. Even if the coercive force of the first ferromagnetic conductive layer 11 is so high that it is difficult to reverse the magnetization of the first ferromagnetic conductive layer 11, the magnetization of the first ferromagnetic conductive layer 11 is reversed without using a current magnetic field. It is possible.

  In the above description of the present invention, the electric field recording type magnetic memories 3100 and 4100 having the heat assist means 81 for heating the first ferromagnetic conductive layer 11 by laser irradiation are exemplified, but the present invention is not limited to this form. . For example, an electric field recording type magnetic memory having a heat assisting means for heating the first ferromagnetic conductive layer by other heating means such as microwave irradiation or surface plasmon resonance may be used.

In the above description of the present invention has been described by way of the field recording magnetic memory 100,1100,2100,3100,4100 form polarization _{P 0} in the same direction of magnetization _{M 0} is induced in the ferromagnetic and ferroelectric layer 12, the The invention is not limited to this form. In the electric field recording magnetic memory of the present invention, for example, a ferromagnetic ferroelectric material in which magnetization in the direction opposite to the polarization is induced may be employed for the ferromagnetic ferroelectric layer. Further, for example, a ferromagnetic ferroelectric material in which magnetization in a direction inclined with respect to polarization is induced may be employed for the ferromagnetic ferroelectric layer.

  In the above description of the present invention, the first ferromagnetic conductive layer 11 has perpendicular magnetic anisotropy, and the magnetic information is magnetized in the direction perpendicular to the surface of the first ferromagnetic conductive layer 11, that is, FIG. However, the present invention is not limited to this mode. For example, an electric field recording type magnetic memory in which the first ferromagnetic conductive layer has in-plane magnetic anisotropy and magnetic information is recorded as magnetization in the in-plane direction of the first ferromagnetic conductive layer. Is also possible.

  In the above description of the present invention, the pair of write electrodes 21 and 22 includes the ferromagnetic ferroelectric layer 12 and the first ferromagnetic conductive layer 11, and the ferromagnetic ferroelectric layer 12 and the first ferromagnetic conductive layer 11. Although the electric field recording type magnetic memory 100 is arranged so as to be sandwiched in the stacking direction, the present invention is not limited to this form. In the electric field recording type magnetic memory according to the present invention, the pair of write electrodes includes, for example, a ferromagnetic ferroelectric layer in a direction crossing the lamination direction of the ferromagnetic ferroelectric layer and the first ferromagnetic conductive layer. You may arrange | position so that it may pinch | interpose. Further, for example, the pair of write electrodes are arranged in contact with the ferromagnetic ferroelectric layer so as to be separated from each other in the longitudinal direction of the recording medium so as to apply an in-plane electric field to the ferromagnetic ferroelectric layer. May be.

  In the above description regarding the present invention, the writing circuit 50, the bit moving circuit 60, and the reading circuit 70 do not share any electrodes, and the electric field recording type magnetic memory 2100, and the writing circuit 50 and the reading circuit 70. Share a single electrode (that is, the read circuit 70 is disposed in contact with the second ferromagnetic conductive layer 42 (or the pinned magnetic conductive layer 43) and the first ferromagnetic conductive layer. The electric field recording type magnetic memories 100, 1100, 3100, and 4100, which are connected to the electrode 21, are illustrated, but the present invention is not limited to these forms. For example, the writing circuit and the bit moving circuit share one electrode (that is, one electrode of the pair of bit moving electrodes and one electrode of the pair of writing electrodes are common) And a mode in which the bit movement circuit and the reading circuit share one electrode (that is, the reading circuit has a second ferromagnetic conductive layer (or a fixed magnetic conductive layer), and An electric field recording type magnetic memory or a writing circuit, a bit moving circuit, and a reading circuit, which are connected to a bit moving electrode disposed in contact with the first ferromagnetic conductive layer. A shared configuration (that is, the reading circuit is connected to the second ferromagnetic conductive layer (or pinned magnetic conductive layer) and the writing electrode disposed in contact with the first ferromagnetic conductive layer. And It is also possible that one electrode of the pair of bit moving electrode is a field recording magnetic memory of one that is common form with) a pair of write electrodes.

100, 1100, 2100, 3100, 4100 Electric field recording type magnetic memory 10, 2010 Recording medium 11 First ferromagnetic conductive layer 12 Ferromagnetic ferroelectric layer 13 Domain walls 21, 22, 21 ′, 22 ′ Writing electrode 21′a 22'a Through-hole 31, 32 Bit moving electrode 41 Nonmagnetic layer 42 Second ferromagnetic conductive layer 43 Fixed magnetic conductive layer 45 Reading counter electrode 50 Writing circuit 60 Bit moving circuit 70 Reading circuit

Claims (10)

A recording medium comprising a first ferromagnetic conductive layer extending one-dimensionally, and a ferromagnetic ferroelectric layer stacked on at least a part of one surface of the first ferromagnetic conductive layer;
A pair of write electrodes for applying an electric field to the ferromagnetic ferroelectric layer;
A pair of bit moving electrodes disposed in contact with the first ferromagnetic conductive layer and spaced apart in the longitudinal direction of the recording medium;
A nonmagnetic layer disposed adjacent to a portion of the surface of the first ferromagnetic conductive layer;
A second ferromagnetic conductive layer disposed on the surface of the nonmagnetic layer and facing the first ferromagnetic conductive layer across the nonmagnetic layer;
By applying an electric field to the ferromagnetic ferroelectric layer through the pair of write electrodes, magnetization in a direction determined corresponding to the direction of the electric field is generated in the ferromagnetic ferroelectric layer, and the ferromagnetic A writing circuit for recording magnetic information in the first ferromagnetic conductive layer by magnetization generated in the ferroelectric layer;
A bit moving circuit that moves a domain wall in the first ferromagnetic conductive layer by passing a current through the first ferromagnetic conductive layer through the pair of bit moving electrodes;
An electric field recording type magnetic memory comprising: a reading circuit that obtains a signal corresponding to an electric resistance between the first ferromagnetic conductive layer and the second ferromagnetic conductive layer. The first ferromagnetic conductive layer is one or a combination of two or more selected from the group consisting of an L2 ₁ type ferromagnetic alloy layer, an L1 ₀ type ferromagnetic alloy layer, and a D0 ₃ type ferromagnetic alloy layer. Item 2. The electric field recording magnetic memory according to Item 1.   The electric field recording magnetic memory according to claim 1, wherein the nonmagnetic layer is an insulating layer. It said second ferromagnetic conductive layer, rutile-type conductive ferromagnetic oxide layer, is 1 or 2 or more combinations selected from the group consisting of L1 ₀ type ferromagnetic alloy layer, and L2 ₁ type ferromagnetic alloy layer The electric field recording type magnetic memory according to claim 1. A pinned magnetic conductive layer is disposed on the surface of the second ferromagnetic conductive layer,
The second ferromagnetic conductive layer is sandwiched between the pinned magnetic conductive layer and the nonmagnetic layer,
The fixed magnetic conductive layer, the antiferromagnetic conductive layer or L1 ₀ type ferromagnetic alloy layer, or a combination thereof,
The electric field recording type magnetic memory according to claim 1. When the write circuit records magnetic information on the first ferromagnetic conductive layer, the write circuit further includes a heat assist means for heating a region where the magnetic information is written in the first ferromagnetic conductive layer.
The electric field recording type magnetic memory according to claim 1.   The pair of write electrodes are arranged so as to sandwich the ferromagnetic ferroelectric layer and the first ferromagnetic conductive layer in the stacking direction of the ferromagnetic ferroelectric layer and the first ferromagnetic conductive layer. The electric field recording type magnetic memory according to claim 1. Said first ferromagnetic conducting layer, a layer of L2 ₁ type ferromagnetic alloy represented by the following composition formula (1), a layer of L1 ₀ type ferromagnetic alloy represented by the following formula (2) and, The electric field recording type magnetic memory according to any one of claims 1 to 7, which is one or a combination of two or more selected from the group consisting of layers of a D0 type ₃ ferromagnetic alloy represented by the following composition formula (3).
X ₂ YZ (1)
(In formula (1), X is one or more elements selected from Fe, Co, and Ni; Y is one or more elements selected from Mn, Cr, V, and Ti; Z is Ge , One or more elements selected from Ga, Si, and Al.)
Mn ₅₀ Ge _x Ga _y Al _50-xy (2)
(In formula (2), x is a real number from 0 to 50; y is a real number from 0 to 50; x and y satisfy x + y ≦ 50.)
X ₃ Y (3)
(In formula (3), X is one or more elements selected from Mn and V; Y is one or more elements selected from Ge, Ga, Si, and Al.) The electric field recording magnetic memory according to claim 1, wherein the ferromagnetic ferroelectric layer includes a ferromagnetic ferroelectric material represented by the following composition formula (5).
_{(Bi 1-a X a)} (Fe 1-b M b) O 3 (5)
(In Formula (5), X is one or more elements selected from Ba and La; M is one or more elements selected from Mn and Ti; a and b are 0 ≦ a ≦ 0. 8 and a real number satisfying 0 ≦ b ≦ 0.5.) It said second ferromagnetic conductive layer, a layer of rutile-type conductive ferromagnetic oxide represented by the composition formula CrO _2, a layer of L1 ₀ type ferromagnetic alloy represented by the following formula (6), and the following The electric field recording type magnetic memory according to any one of claims 1 to 9, which is one or a combination of two or more selected from the group consisting of L2 type ₁ ferromagnetic alloy layers represented by the composition formula (7).
XY (6)
(In Formula (6), X is one or more elements selected from Fe and Co; Y is one or more elements selected from Pt, Pd, and Ni.)
X ₂ YZ (7)
(In Formula (7), X is one or more elements selected from Fe, Co, and Ni; Y is one or more elements selected from Mn, Cr, V, and Ti; Z is Ge , One or more elements selected from Ga, Si, and Al.)

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