WO2018041188A1

WO2018041188A1 - Leakage-free, low-loss waveguide having fast mode at magnetic surface of magneto-optical gap thereof and being unidirectionally flexible to any angle

Info

Publication number: WO2018041188A1
Application number: PCT/CN2017/099826
Authority: WO
Inventors: 欧阳征标; 郑耀贤
Original assignee: 深圳大学
Priority date: 2016-08-31
Filing date: 2017-08-31
Publication date: 2018-03-08
Also published as: CN106200026B; CN106200026A

Abstract

A leakage-free, low-loss waveguide having a fast mode at a magnetic surface of a magneto-optical gap thereof and being unidirectionally flexible to any angle comprises: a light input port (1); a light output port (2); two magneto-optical material layers (3, 4); a dielectric layer (5); four wave-absorbing layers (6, 7, 8, 9); and two bias magnetic fields (H₀). The two bias magnetic fields (H₀) are arranged in opposite directions, and the orientation thereof can be controlled. The two magneto-optical material layers (3, 4) and the dielectric layer (5) form an optical waveguide having a three-layer structure bendable to any angle. The two bias magnetic fields (H₀), which are arranged in opposite directions and the orientation thereof can be controlled, are provided at the magneto-optical material layers (3, 4). A gap between the magneto-optical material layers (3, 4) is the dielectric layer (5). A port (1) of the unidirectionally bendable waveguide is a light input port (1), and a port (2) of the unidirectionally bendable waveguide is the light output port (2). The dielectric layer (5) has a ring-shaped portion at where the waveguide bends. A magnetic surface fast-wave exists at a surface between the magneto-optical material layers (3, 4) and the dielectric layer (5). The invention has a simple structure and high transmission efficiency, and is suitable for large-scale optical integrated circuits.

Description

Leak-free low-loss magneto-optical gap magnetic surface fast mode controllable one-way arbitrary bend waveguide

Technical field

The invention relates to a magneto-optical material, a surface wave and a photodiode, in particular to a low-loss magneto-optical magnetic surface fast mode controllable unidirectional arbitrary bending waveguide.

Background technique

A curved waveguide is an optical device used as a conversion optical path, which occupies an important position in an optical waveguide device. Bending in the optical waveguide is necessary due to the change in the direction of beam propagation in the optical waveguide, the displacement of the beam transmission axis, and the need to reduce the volume of the device. The bending of the waveguide causes a change in the optical characteristic distribution of the waveguide material in the direction of light transmission, so that the curved waveguide has a high loss. The field of turning waveguides has been extensively studied, and the curved turning type curved waveguide is the main content of this research. But even for this type of waveguide, the bending loss and transition loss that are present still severely restrict the transmission efficiency. In addition, structural defects and the like can also cause other losses to the waveguide.

Photodiodes and isolators are optics that only allow light to travel in one direction and are used to prevent unwanted light feedback. The main component of conventional photodiodes and isolators is the Faraday rotator, which applies the Faraday effect (magneto-optical effect) as its working principle. Conventional Faraday isolators consist of a polarizer, a Faraday rotator, and an analyzer. This device is complex in structure and is commonly used in free-space optical systems. For integrated optical paths, integrated optical devices such as fiber optics or waveguides are non-polarization-maintaining systems that cause loss of polarization angle and are therefore not suitable for use with pull-up isolators.

Summary of the invention

The object of the present invention is to overcome the deficiencies in the prior art, and provide a leakage-free low-loss magneto-optical magnetic surface fast-mode controllable single with simple structure, low loss, high optical transmission efficiency, small volume, and easy integration. Fly to any bend.

The object of the present invention is achieved by the following technical solutions.

The invention has no leakage and low loss magneto-optical gap magnetic surface fast mode controllable one-way arbitrary bending waveguide including an optical input port 1, an optical output port 2, two magneto-

optical material layers

3, 4, a dielectric layer 5, four

Absorbing layers

6, 7, 8 and 9 and two opposite bias magnetic fields, and the direction is controllable; said magneto-

optical material layers

3, 4 and dielectric layer 5 are a three-layer optical waveguide, said three layers The structure is curved at an arbitrary angle, and two opposite bias magnetic fields are disposed at the magneto-

optical material layers

3 and 4, and the direction is controllable; the gap between the magneto-

optical material layers

3 and 4 is the dielectric layer 5 The port 1 of the unidirectional turning waveguide is an optical input port, and the port 2 is a light output port; the dielectric layer 5 is annular in a curved portion of the waveguide; the magneto-

optical material layers

3, 4 and the dielectric layer 5 The surface is a magnetic surface fast wave.

The photodiode and the isolator are composed of magneto-

optical material layers

3, 4 and a dielectric layer 5.

The magneto-optical material is magneto-optical glass or various rare earth element-doped garnets and rare earth-transition metal alloy films.

The magneto-

optical material layers

3, 4 and the dielectric layer 5 are connected to the optical input port 1 and the light output port 2 by any angular bending.

The dielectric layer is a vacuum, air, silica or a working wave transparent plastic.

The three-layer structure is a flat structure.

The arbitrary angle curved shape is a 30 degree turn shape, a 45 degree turn shape, and a 60 degree turn Curved shape, 90 degree turn shape, 120 degree turn shape, 135 degree turn shape, 150 degree turn shape or 180 degree turn shape.

The absorbing

layers

6, 7, 8, and 9 are the same or different absorbing materials; the absorbing materials are polyurethane, graphite, graphene, carbon black, carbon fiber epoxy resin mixture, graphite thermoplastic material mixture, Boron fiber epoxy resin mixture, graphite fiber epoxy resin mixture, epoxy polysulfide, silicone rubber, urethane, fluoroelastomer, polyetheretherketone, polyethersulfone, polyarylsulfone or polyethyleneimine.

The absorbing

layers

6, 7, 8, and 9 are each at a distance of 1/4 to 1/2 wavelength from the surface of the flat waveguide; the thicknesses of the absorbing

layers

6, 7, 8, and 9 are respectively not Less than 1/4 wavelength.

The bias magnetic field is generated by a current direction controllable electromagnet or a permanent magnet, and the permanent magnet can rotate; the direction controllable curved waveguide or the unidirectional curved waveguide is composed of a magneto-optical gap waveguide; and the working mode of the one-way curved waveguide For the TE mode.

The invention is suitable for large-scale optical path integration and has wide application prospects. Compared with the prior art, it has the following positive effects.

1. The structure is simple and easy to implement.

2. Small size for easy integration.

3. Magnetic surface waves have immune characteristics to structural defects, have ultra-low loss and ultra-high transmission efficiency, and are widely used in the design of various optical waveguides.

DRAWINGS

1 is a structural diagram of a non-leakage low loss magneto-optical magnetic surface fast mode controllable unidirectional arbitrary bend waveguide.

In the figure: optical input port 1 optical output port 2 first magneto-optical material layer 3 second magneto-optical material layer 4 dielectric layer 5 first absorbing layer 6 second absorbing layer 7 second absorbing layer 8 second absorbing wave Layer 9 Biasing field ⊙H ₀ (outer) Biasing field ⊕H ₀ (Li) Thickness of the dielectric layer w Distance between the absorbing layer and the waveguide w ₁ Radius of the inner arc of the ring r Outer arc of the ring Radius r+w.

2 is a first working principle diagram of a non-leakage low loss magneto-optical magnetic surface fast mode controllable one-way arbitrary corner waveguide conduction.

FIG. 3 is a second working principle diagram of the non-leakage low loss magneto-optical magnetic surface fast mode controllable one-way arbitrary turning waveguide conduction.

Fig. 4 is a graph showing a first embodiment of the forward-reverse transmission efficiency of the magneto-optical gap unidirectional turning waveguide as a function of the optical frequency.

Fig. 5 is a graph showing a second embodiment of the forward-reverse transmission efficiency of the magneto-optical gap unidirectional turning waveguide as a function of the optical frequency.

Fig. 6 is a graph showing a third embodiment of the forward-reverse transmission efficiency of the magneto-optical gap unidirectional turning waveguide as a function of the optical frequency.

Fig. 7 is a graph showing a fourth embodiment of the forward-reverse transmission efficiency of the magneto-optical gap unidirectional turning waveguide as a function of the optical frequency.

detailed description

As shown in FIG. 1, the leakage-free low-loss magneto-optical magnetic surface fast mode controllable unidirectional arbitrary bending waveguide of the present invention comprises an optical input port 1, an optical output port 2, and a first magneto-optical material layer 3. a second magneto-optical material layer 4, a dielectric layer 5, a first absorbing layer 6, a second absorbing layer 7, a third absorbing layer 8 and a fourth absorbing layer 9, and two opposite bias magnetic fields H ₀ ; the unidirectional turning waveguide is composed of a magneto-optical gap waveguide, the working mode of the unidirectional turning waveguide is TE mode, and the first magneto-optical material layer 3, the second magneto-optical material layer 4 and the dielectric layer 5 are a three-layer optical waveguide. The optical waveguide can transmit optical signals in one direction, and is used as a photodiode and an isolator. The photodiode and the isolator are composed of a first magneto-optical material layer 3, a second magneto-optical material layer 4, and a dielectric layer 5. The turning angle may be an angle between 0 degrees and 180 degrees, and the bending angle of the unidirectional turning waveguide may also be: an angle between 0 degrees and 180 degrees; for example: 30 degrees, 45 degrees, 60 degrees, 90 degrees, 120 degrees Degrees, 135 degrees, 150 degrees and 180 degrees. Figure 1 (a) one-way turning angle is 30 degrees, Figure 1 (b) one-way turning angle is 45 degrees, Figure 1 (c) one-way turning angle is 60 degrees, Figure 1 (d), (i) single The turning angle is 90 degrees, the one-way turning angle of Figure 1 (e) is 120 degrees, the one-way turning angle of Figure 1 (f) is 135 degrees, the one-way turning angle of Figure 1 (g) is 150 degrees, and Figure 1 ( h) The one-way turning angle is 180 degrees. The three-layer structure is a flat waveguide structure, and the three-layer structure is curved at an arbitrary angle, and the shape bent at an arbitrary angle is a circular arc shape (arc-shaped turning type curved waveguide), for example, when the turning angle is 45 degrees, it is eight points. One ring; when the turning angle is 90 degrees, it is a quarter ring; when the turning angle is 180 degrees, it is a half ring, etc., and so on. Since the device structure of the present invention satisfies the symmetry conservation, that is, its corresponding mirror structure can also work effectively, both of the structures of FIGS. 1(d) and (i) are mirror-symmetrical and have the same operational characteristics. The first magneto-optical material layer 3, the second magneto-optical material layer 4, and the dielectric layer 5 are connected to the optical input port 1 and the optical output port 2 by an arbitrary angular bending shape. The dielectric layer 5 is a region where the light energy is mainly concentrated, and the gap between the first magneto-optical material 3 and the second magneto-optical material 4 is the dielectric layer 5, and the dielectric layer 5 has a ring shape in the curved portion of the waveguide, and the inner arc of the ring The radius is r, the outer arc radius is r+w, the length of the curved portion depends on the turning angle; the dielectric layer 5 is vacuum, air, silicon dioxide (glass) or a transparent plastic working wave. The magneto-

optical material layers

3, 4 and the dielectric layer 5 constitute a photodiode and an isolator capable of unidirectionally transmitting optical signals, and the magneto-

optical materials

3, 4 and the surface of the dielectric layer 5 are magnetic surface fast waves. The magneto-optical material is magneto-optical glass or various rare earth-doped garnets and rare earth-transition metal alloy films. The first magneto-optical material layer 3 and the second magneto-optical material layer 4 are respectively provided with bias magnetic fields H _{0 in} opposite directions, that is, a bias magnetic field ⊙H ₀ (outer) and a bias magnetic field ⊕H ₀ (in), The magnetic field H ₀ is generated by an electromagnet whose current direction is controllable or by a rotatable permanent magnet, so that the direction of the current can be controlled to change the conduction direction of the waveguide or by rotating the permanent magnet. When the static magnetic field H ₀ to the drawing surface 3 outward perpendicular to the first magneto-optical material layer is applied, and the second magneto-optical material 4 is applied perpendicular to the static magnetic field H ₀ in the layer facing the inside of the paper, one-way turning port optical waveguide 1 At the input end, port 2 is an optical output port, and port 1 to port 2 are turned on; when the first magneto-optical material layer 3 is applied with a static magnetic field H ₀ perpendicular to the paper surface, and the second magneto-optical material layer 4 is applied perpendicular to the paper. When the static magnetic field H ₀ is outward, port 2 of the one-way cornering waveguide is an optical input port, port 1 is an optical output port, and port 2 to port 1 are turned on. The first absorbing layer 6, the second absorbing layer 7, the third absorbing layer 8 and the fourth absorbing layer 9 are the same or different absorbing materials, and the absorbing materials are polyurethane, graphite, graphene, carbon black, Carbon fiber epoxy resin mixture, graphite thermoplastic material mixture, boron fiber epoxy resin mixture, graphite fiber epoxy resin mixture, epoxy polysulfide, silicone rubber, urethane, fluoroelastomer, polyether ether ketone, poly Ether sulfone, polyaryl sulfone or polyethylene imine. The first absorbing layer 6, the second absorbing layer 7, the third absorbing layer 8, and the fourth absorbing layer 9 are each at a distance of 1/4 to 1/2 wavelength from the surface of the flat waveguide, and the first absorbing wave The thicknesses of the layer 6, the second wave absorbing layer 7, the third wave absorbing layer 8, and the fourth wave absorbing layer 9 are each not less than 1/4 wavelength, respectively.

The magnetic surface wave generated by the magneto-optical material-medium interface is a phenomenon similar to the metal surface plasmon (SPP). Under the action of the biased static magnetic field, the magneto-optical material has a magnetic permeability of tensor, and at the same time, its effective refractive index is negative in a certain optical band. Thus, the surface of the magneto-optical material is capable of producing a guided wave and has a property of unidirectional propagation, which is called a surface acoustic wave (Surface Magnetically Polarized Wave, SMP).

The invention relates to a non-leakage low loss type magneto-optical gap magnetic surface fast mode arbitrary angle one-way cornering waveguide. The device is based on the non-reciprocity of the magneto-optical material, and the surface light can be generated by combining the magneto-optical material-medium interface. The characteristics of the unidirectional turning waveguide with excellent performance. The combination of a magneto-optical material-medium-magneto-optical material three-layer structure waveguide and four absorbing layers enables a magnetic surface fast wave generated by a magneto-optical material-medium interface to perform unidirectional bending transmission of light, using a current-controlled electromagnetic Iron controls the conduction direction of the waveguide, that is, the direction of the bias magnetic field determines the conduction direction of the curved waveguide, and the turning angle can be arbitrarily set. At the same time, the absorbing layer absorbs unwanted waves and eliminates optical path interference.

The technical scheme of the invention realizes the design of the controllable unidirectional turning waveguide based on the optical non-reciprocity of the magneto-optical material and the unique conductive surface wave characteristic of the magneto-optical material-medium interface. The basic principles of this technical solution are as follows:

The magneto-optical material is a material having magnetic anisotropy, and the magnetic dipole inside the magneto-optical material is arranged in the same direction by the application of a static magnetic field, thereby generating a magnetic dipole moment. The magnetic dipole moment will interact strongly with the optical signal, which in turn produces a non-reciprocal transmission of light. The magnetic permeability tensor of the magneto-optical material is under the action of a bias magnetic field H ₀ oriented in the direction perpendicular to the vertical paper:

The matrix elements of the permeability tensor are given by the following equations:

Where μ ₀ is the magnetic permeability in vacuum, γ is the gyromagnetic ratio, H ₀ is the applied magnetic field, M _s is the saturation magnetization, ω is the operating frequency, and α is the loss coefficient. If the direction of the biasing magnetic field is changed to the vertical paper facing direction, H ₀ and M _s will change the sign.

The magnetic surface waves generated by the magneto-optical material and the interface of the medium can be solved according to the magnetic permeability tensor of the magneto-optical material and Maxwell's equations. The electric and magnetic fields that satisfy the surface wave (which is a TE wave) at the interface should have the following form:

Where i=1 represents the magneto-optical material region and i=2 represents the dielectric region. Substituting Maxwell's equations:

According to the constitutive relation and the boundary conditions, the transcendental equation about the wave vector k _z of the magnetic surface wave can be obtained:

among them,

It is the effective permeability of magneto-optical materials. This transcendental equation can be solved by a numerical solution, and finally the value of k _z is obtained. It can also be seen from the equation that since the equation contains the term of μ _κ k _z , the surface acoustic wave has non-reciprocity (one-way propagation).

It can be seen that if a three-layer structure of a magneto-optical material-medium-magneto-optical material is used, a magnetic field in the opposite direction is disposed at the first magneto-optical material layer 3 and the second magneto-optical material layer 4, and the direction of the magnetic field of the electromagnet is controlled by the current. , then will constitute an effective controllable one-way cornering waveguide. And due to the characteristics of the surface acoustic wave (SMP), the curved waveguide will theoretically have no loss due to the curved structure. As shown in Fig. 2, yttrium iron garnet (YIG) is used as the magnetic anisotropic material, the dielectric layer is air (n ₀ =1), the bias magnetic field is 900 Oe, the dielectric layer thickness is w=5 mm, and the first absorbing wave The distance between the layer 6, the second absorbing layer 7, the third absorbing layer 8 and the fourth absorbing layer 9 and the waveguide respectively is w ₁ = 5 mm, the radius of the arc is r = 30 mm, and the operating frequency f of the device is magnetic The dielectric constants ε ₁ , ε ₂ and magnetic permeability [μ ₁ ] of the optical material and medium are determined by μ ₂ , the operating frequency is f=6 GHz, the YIG material loss coefficient α=3×10 ^-4 , and the turning angle is 90 °. When the direction of the magnetic field at the first magneto-optical material layer 3 is perpendicular to the paper, and the direction of the magnetic field at the second magneto-optical material layer 4 is perpendicular to the paper, if the light is input from the port 1, it will be simultaneously at the two magneto-optical materials. - The medium interface generates a unidirectional forward-transferred magnetic surface wave, and finally outputs it from port 2. If the light is input from port 2, the light wave cannot be reversely transmitted inside the device due to the non-reciprocity of the surface acoustic wave, thereby failing to Port 1 output, the light energy has all been blocked at input port 2. At the same time, it can be seen that the light wave can be well confined to the curved waveguide, and the loss value is very low. The conduction direction of the curved waveguide is determined by the direction of the applied magnetic field. When the direction of the magnetic field applied at the first magneto-optical material layer 3 and the second magneto-optical material layer 4 is simultaneously changed, as shown in FIG. 3, the yttrium iron garnet is used. (YIG) as a magnetic anisotropic material, the dielectric layer 5 is air (n ₀ =1), the bias magnetic field size is 900 Oe, the dielectric layer thickness is w=5 mm, the first absorbing layer 6, the second absorbing layer 7, The distance between the third absorbing layer 8 and the fourth absorbing layer 9 and the waveguide is respectively w ₁ = 5 mm, the radius of the inner arc of the ring is r = 30 mm, and the operating frequency f of the device is defined by the magneto-optical material and the medium. The electric constants ε ₁ , ε ₂ and magnetic permeability [μ ₁ ], determined by μ ₂ , the operating frequency is f = 6 GHz, the YIG material loss coefficient α = 3 × 10 ^-4 , the turning angle is 90 °, the first magneto-optical The magnetic field at the material 3 is in the direction of the vertical paper, and the magnetic field at the second magneto-optical material 4 is the outer side of the vertical paper, and the conduction direction of the curved waveguide is opposite. When the light wave is input from port 2, a magnetic surface wave can be generated inside the device, and then output from port 1; when the light wave is input from port 1, the reverse light wave cannot be propagated inside due to the non-reciprocity of the device, port 2 Without any light output, the light energy is all blocked at input port 1.

The leakage-free low-loss magneto-optical magnetic surface fast mode controllable unidirectional arbitrary cornering waveguide of the device of the invention has three-layer structural characteristics of a magneto-optical material-medium-magneto-optical material, and its structural size and parameters, such as the inner circle of the ring The arc radius r and the dielectric layer thickness w can be flexibly selected according to the operating wavelength and actual demand. Changing the size has no major impact on device performance.

Four embodiments are given below with reference to the accompanying drawings. In the embodiment, YAG is used as the magnetic anisotropic material, the bias magnetic field is 900 Oe, and the dielectric layer 5 is air (n ₀ =1). The thickness of the layer 5 is w=5 mm, the radius of the inner arc of the ring is r=30 mm, and the first absorbing layer 6, the second absorbing layer 7, the third absorbing layer 8 and the fourth absorbing layer 9 are respectively connected to the waveguide. The distance between them is w ₁ = 5 mm, the operating frequency is f = 6 GHz f, and the YIG material loss coefficient α = 3 × 10 ^-4 .

Example 1

Referring to FIG. 1(b), the direction-controllable turning waveguide is composed of a magneto-optical gap waveguide, and the corner is turned The degree is 45 degrees. In the working frequency band, the direction of the magnetic field at the first magneto-optical material layer 3 is controlled by the electromagnet current, and the direction of the magnetic field at the second magneto-optical material layer 4 is perpendicular to the paper surface, and the curved waveguide will be from port 1 to port. 2 is turned on; on the contrary, the direction of the magnetic field at the first magneto-optical material 3 is controlled to be perpendicular to the paper, and the direction of the magnetic field at the second magneto-optical material 4 is perpendicular to the paper, and the curved waveguide will be turned on from the port 2 to the port 1. In both cases, the forward and reverse transmissions have the same efficiency. Referring to Figure 4, the operating frequency range of the directionally controllable cornering waveguide is 4.99 GHz to 7.29 GHz. In the operating frequency range, considering the material loss, the direction-controlled cornering waveguide has a maximum forward-reverse transmission isolation of 23.215 dB and a forward transmission insertion loss of 0.0228 dB.

Example 2

Referring to Figures 1(d) and (i), the unidirectional turning waveguide is composed of a magneto-optical gap waveguide having a turning angle of 90 degrees. In the working frequency band, the direction of the magnetic field at the first magneto-optical material layer 3 is controlled by the electromagnet current, and the direction of the magnetic field at the second magneto-optical material layer 4 is perpendicular to the paper surface, and the curved waveguide will be from port 1 to The port 2 is turned on; on the contrary, the magnetic field direction of the first magneto-optical material layer 3 is controlled to be perpendicular to the paper surface, the magnetic field direction of the second magneto-optical material layer 4 is perpendicular to the paper, and the curved waveguide is turned on from the port 2 to the port 1. . In both cases, the forward and reverse transmissions have the same efficiency. Referring to Figure 5, the operating frequency range of the directionally controllable cornering waveguide is 5.04 GHz to 7.44 GHz. In the operating frequency range, considering the material loss, the direction-controlled cornering waveguide has a maximum forward-reverse transmission isolation of 25.513 dB and a forward transmission insertion loss of 0.0123 dB.

Example 3

Referring to FIG. 1(f), the unidirectional turning waveguide is composed of a magneto-optical gap waveguide, and the turning angle is 135 degrees. In the working frequency band, the direction of the magnetic field at the first magneto-optical material layer 3 is controlled by the electromagnet current, and the direction of the magnetic field at the second magneto-optical material layer 4 is perpendicular to the paper surface, and the curved waveguide will be from port 1 to port. 2 is turned on; on the contrary, the magnetic field direction of the first magneto-optical material layer 3 is controlled to be perpendicular to the paper surface, and the magnetic field direction of the second magneto-optical material layer 4 is perpendicular to the paper surface, and the curved waveguide will be turned on from the port 2 to the port 1. In both cases, the forward and reverse transmissions have the same efficiency. Referring to Figure 6, the operating frequency range of the directionally controllable cornering waveguide is 5.05 GHz to 7.41 GHz. In the operating frequency range, considering the material loss, the direction-controlled cornering waveguide has a maximum forward-reverse transmission isolation of 23.372 dB and a forward transmission insertion loss of 0.0200 dB.

Example 4

Referring to Fig. 1(h), the one-way cornering waveguide is composed of a magneto-optical gap waveguide with a turning angle of 180 degrees. In the working frequency band, the direction of the magnetic field at the first magneto-optical material layer 3 is controlled by the electromagnet current, and the direction of the magnetic field at the second magneto-optical material layer 4 is perpendicular to the paper surface, and the curved waveguide will be from port 1 to port. 2 is turned on; on the contrary, the magnetic field direction of the first magneto-optical material layer 3 is controlled to be perpendicular to the paper surface, and the magnetic field direction of the second magneto-optical material layer 4 is perpendicular to the paper surface, and the curved waveguide will be turned on from the port 2 to the port 1. In both cases, the forward and reverse transmissions have the same efficiency. Referring to Figure 7, the operating frequency range of the directionally controllable cornering waveguide is from 4.99 GHz to 7.33 GHz. In the operating frequency range, considering the material loss, the direction-controlled cornering waveguide has a maximum forward-reverse transmission isolation of 27.545 dB and a forward transmission insertion loss of 0.00765 dB.

The transmission efficiency curve of the magneto-optical gap magnetic surface fast mode unidirectional turning waveguide with different turning angles shown in Fig. 4, Fig. 5, Fig. 6 and Fig. 7 can be transmitted by the magneto-optical gap turning waveguide. The optical frequency range of the magnetic surface fast wave, that is, the operating frequency range of the unidirectional turning waveguide. It can be seen from the results that the leakage-free low-loss magneto-optical magnetic surface fast mode controllable one-way arbitrary curved waveguide of the present invention can work effectively.

The invention described above is susceptible to modifications of the specific embodiments and applications, and should not be construed as limiting the invention.

Claims

A leakage-free low-loss magneto-optical gap magnetic surface fast mode controllable unidirectional arbitrary cornering waveguide, characterized in that it comprises an optical input port (1), an optical output port (2), and two layers of magneto-optical materials ( 3, 4), a dielectric layer (5), four absorbing layers (6), (7), (8) and (9) and two opposite bias magnetic fields, and the direction is controllable; The light material layer (3, 4) and the dielectric layer (5) are a three-layer structure optical waveguide, the three-layer structure is curved at an arbitrary angle, and two are disposed at the magneto-optical material layer (3, 4) a bias magnetic field in opposite directions, and the direction is controllable; a gap between the layers of magneto-optical material (3, 4) is a dielectric layer (5), and a port (1) of the unidirectional curved waveguide is an optical input port, The port (2) is a light output port; the dielectric layer (5) is in the shape of a ring in the curved portion of the waveguide; the surface of the magneto-optical material (3, 4) and the surface of the dielectric layer (5) are magnetic surface fast waves .
The leak-free low-loss magneto-optical gap magnetic surface fast mode controllable unidirectional arbitrary bend waveguide according to claim 1, wherein the photodiode and the isolator are composed of a layer of magneto-optical material (3, 4) and a dielectric layer (5) ) constitutes.
The leakage-free low-loss magneto-optical magnetic surface fast mode controllable unidirectional arbitrary cornering waveguide according to claim 1, wherein the magneto-optical material is magneto-optical glass or various rare earth doped garnets and rare earths. - Materials such as transition metal alloy films.
The leakage-free low-loss magneto-optical magnetic surface fast mode controllable unidirectional arbitrary cornering waveguide according to claim 1, wherein said magneto-optical material layer (3, 4) and dielectric layer (5) pass any angle The curved shape is connected to the optical input port (1) and the optical output port (2).
The leakage-free low-loss magneto-optical gap magnetic surface fast mode controllable according to claim 1 A unidirectional arbitrary curved waveguide, characterized in that the dielectric layer (5) is a vacuum, air, silicon dioxide or a working wave transparent plastic.
The leak-free low-loss magneto-optical gap magnetic surface fast mode controllable unidirectional arbitrary bend waveguide according to claim 1, wherein the three-layer structure is a flat waveguide structure.
The leakage-free low-loss magneto-optical magnetic surface fast mode controllable unidirectional arbitrary cornering waveguide according to claim 1, wherein the arbitrary angle curved shape is a 30-degree curved shape, a 45-degree curved shape, and a 60-degree curved shape. Shape, 90 degree turn shape, 120 degree turn shape, 135 degree turn shape, 150 degree turn shape, 180 degree turn shape.
The leakage-free low-loss magneto-optical magnetic surface fast mode controllable unidirectional arbitrary cornering waveguide according to claim 1, wherein said absorbing layers (6), (7), (8) and (9) The same or different absorbing materials; the absorbing materials are polyurethane, graphite, graphene, carbon black, carbon fiber epoxy resin mixture, graphite thermoplastic material mixture, boron fiber epoxy resin mixture, graphite fiber epoxy Resin mixture, epoxy polysulfide, silicone rubber, urethane, fluoroelastomer, polyetheretherketone, polyethersulfone, polyarylsulfone or polyethyleneimine.
The leakage-free low-loss magneto-optical magnetic surface fast mode controllable unidirectional arbitrary cornering waveguide according to claim 1, wherein said absorbing layers (6), (7), (8) and (9) The distance from the surface of the flat waveguide is 1/4 to 1/2 wavelength, respectively; the thickness of the absorbing layers (6), (7), (8) and (9) are not less than 1/4 respectively. wavelength.
The leakage-free low-loss magneto-optical gap magnetic surface fast mode controllable unidirectional arbitrary-bending waveguide according to claim 1, wherein the bias magnetic field is generated by a current-direction controllable electromagnet or a permanent magnet, and the permanent magnet can Rotation; the direction of the controllable cornering waveguide or one way The cornering waveguide is composed of a magneto-optical gap waveguide; the unidirectional cornering waveguide operates in a TE mode.