SU721851A1 - Method of recording from cylindrical magnetic domains - Google Patents

Description

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in the nfifrrionH of two neighboring houses, noBbiiiKve Q-factors) of the esoil circuits by increasing the frequency of the formromptine resonance leads to a sharp complication of the device as a whole. In addition, the frequency r} to the rhythm and the rr-zone (FMR) strongly depends both on the magnetic field of the CMD and on the external control magnetic fields, and the sensitivity of the device for indicating and detecting the CMD of micron and submicron sizes is insufficient to ensure the levels of output signals sufficient for their further processing. A device that implements this method is difficult in design and technology.

The aim of the invention is to increase the output signal level and the signal-to-interference ratio when reading the CMD.

The goal is achieved by exciting a galvanomagnetic resonance in a thin ferromagnetic film, and the frequency of the alternating current is chosen equal to the frequency of its own ferromagnetic resonance of a thin ferromagnetic film.

The drawing shows a device for reading CMD, designed to implement the proposed method of reading CMD.

The device for reading the CMD contains a magnetically uniaxial film with the CMD 1 on which the second high-frequency device 2 is located, which is the sensitive element of the reading of the CMD. The sensing element is a thin ferromagnetic film with contact leads 3 the length of the supply to the element 2 of a constant or alternating electric field (voltage). The axis of easy magnetization (OLI) of the sensitive element coincides with the direction of the current density vector. Through the insulating and diamagnetic film 4, the sensitive element (the second high-frequency yctff) is magnetically coupled to the magnetic flux of the high-frequency magnetic field created by the high-frequency current of the first high-frequency device 5, which is made in the form of a thin-film hinge (loop), which is arranged in such a way that The magnet of the priest created by it was parallel to the axis of the difficult magnetization of the sensitive element 2.

The device is operating with a blind device.

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When there is no CMD, the second high-frequency device does not separate the signal, since the magnetization M is parallel to the input current density vector J, and the amplitude of the RF-magnetic field of the first high-frequency device 5 is not enough to magnetize the sensitive element in the direction of the solid magnetization axis. At the moment when the CMD passes near the device, the sensitive element of the second high-frequency device 2 re-magnetizes in the direction of the OTN (MP OTN) and in it the FMR is excited with a frequency w determined by the field of the NzmA domain and the anisotropy field H.

If the frequency of the high-frequency magnetic field H coincides with the COQ, a resonant voltage peak appears at the output of the device, which is the read signal of the CMD. In the absence of CMD in the anisotropy field, returns the vector M in the direction of the EA.

Thus, the device realizes the effect of galvanomagnetic resonance and can be effectively used to create sensitive devices and information output systems in the domain memory. Since the level of interference in the implementation of the proposed method does not exceed this value in the known method of reading a CMD, the signal-to-noise ratio in the proposed method of reading a CMD is a factor higher.

The proposed invention can be used for reading CMD micron to submicron sizes with output levels of 3-5 mV without increasing the size of the CMD, as well as for detecting weak magnetic fluxes in measuring equipment devices.

Claims (2)

1.AjiropCKof sgm1dogol 1snyi S (T1 according to the application jN 253754-1 / 1H-24, cl. G 11 C 7/00, 10.25.77. 2. US patent number 3980181, cl. 34O-174, 1976 (prototype). / 2 О®®® О®®. five