WO2016015629A1 - 基于光子晶体波导的超高效紧凑十字型环行器 - Google Patents

基于光子晶体波导的超高效紧凑十字型环行器 Download PDF

Info

Publication number
WO2016015629A1
WO2016015629A1 PCT/CN2015/085345 CN2015085345W WO2016015629A1 WO 2016015629 A1 WO2016015629 A1 WO 2016015629A1 CN 2015085345 W CN2015085345 W CN 2015085345W WO 2016015629 A1 WO2016015629 A1 WO 2016015629A1
Authority
WO
WIPO (PCT)
Prior art keywords
photonic crystal
dielectric
refractive index
silicon
column
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2015/085345
Other languages
English (en)
French (fr)
Inventor
欧阳征标
金鑫
林密
王琼
文国华
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shenzhen University
Original Assignee
Shenzhen University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shenzhen University filed Critical Shenzhen University
Publication of WO2016015629A1 publication Critical patent/WO2016015629A1/zh
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
    • G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
    • G02B6/122—Basic optical elements, e.g. light-guiding paths
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/09—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on magneto-optical elements, e.g. exhibiting Faraday effect

Definitions

  • the invention relates to the field of four-port cross-type circulators, in particular to a cross-type looper based on photonic crystal technology.
  • circulators Since the birth of electromagnetism, circulators have been widely used for their unique functions.
  • the circulator can be applied to different bands and devices depending on the application.
  • the signal When used as an isolator, the signal can be transmitted in only one direction by shielding the signal from the output; in radar technology, the circulator can loop the signal from the transmitter to the antenna, and then from the antenna to the receiver.
  • the function of the duplexer is implemented; in the reflection amplifier, the circulator acts as a non-reciprocal device to separate the amplified output signal from the input.
  • photonic crystal waveguides are considered to be a medium that can efficiently transmit electromagnetic waves. Therefore, photonic crystal waveguide theory has opened up new fields for exploring high-efficiency microwave integrated circuits and integrated optical paths.
  • microwave device and an integrated optical path that integrates a large number of components various echo interferences are inevitably generated between the components to affect the functions of the entire system. Therefore, minimizing these disturbances will be a top priority for optimizing the entire system.
  • a ferrite-based photonic crystal waveguide circulator is a non-reciprocal device that allows waves to propagate in a single direction, while a back-propagated wave is introduced into another waveguide.
  • photonic crystal waveguide-based circulators have been designed to be much smaller and have better performance than conventional magneto-optical circulators, most designs use multiple magneto-optical dielectric columns or couplings.
  • the dielectric column acts directly with the wavefront, so the structure is still relatively complex and the bandwidth is relatively narrow.
  • the photonic crystal waveguide based ultra-efficient compact cross type circulator of the present invention comprises a a four-port cross-shaped photonic crystal waveguide; a center of the cross-shaped photonic crystal waveguide is placed with a square magneto-optical dielectric rod; and the four corners at the center of the cross-waveguide are respectively provided with four square dielectric rod chamfers
  • the photonic crystal is formed by periodically arranging the high refractive index dielectric rods in the background of the low refractive index medium, or by periodically arranging the low refractive index dielectric rods in the background of the high refractive index medium.
  • the high refractive index dielectric material is a medium having a refractive index greater than 2 such as silicon, gallium arsenide, titanium dioxide or silicon nitride, and the low refractive index dielectric material is air, vacuum, silicon dioxide, cryolite, olive oil or refractive index less than 1.6 media.
  • the input wave of any input end of the photonic crystal waveguide is looped clockwise or counterclockwise to an adjacent output waveguide port orthogonal to the input end waveguide by 90 degrees, and the direction of the electromagnetic wave is changed with the direction of the applied magnetic field.
  • the magneto-optical medium rod is a ferrite material.
  • the cross section of the magneto-optical dielectric rod is square, rectangular, circular, elliptical, circular, pentagonal, hexagonal, arbitrary polygonal, and any closed curve.
  • the four corner dielectric rods have a triangular, semi-circular, semi-elliptical, semi-polygonal, or closed pattern formed by straight edges and curves.
  • the cross section of the background dielectric column of the photonic crystal cross waveguide is triangular, circular, semi-circular, elliptical, semi-elliptical, polygonal, or closed.
  • the high refractive index dielectric material is silicon
  • the low refractive index dielectric material is air
  • the photonic crystal is periodically arranged by silicon in an air background, and the radius of the silicon dielectric column in the photonic crystal is 0.3a, normalized
  • the frequency is 0.4121
  • the separation factor is 0.7792
  • the length of the magneto-optical medium column is 0.2817a
  • the center distance of the corner dielectric column is 1.2997a
  • the insertion loss of the circulator is 0.02dB, where a is the lattice constant of the photonic crystal.
  • the separation factor is the ratio of the absolute value of the second row of the relative permeability tensor of the magneto-optical medium to the value of the first element of the first row, the normalized frequency is ⁇ a/2 ⁇ c, and ⁇ is the circular frequency.
  • c is the speed of light in the vacuum;
  • the high refractive index dielectric material is silicon
  • the low refractive index dielectric material is air
  • the photonic crystal is periodically arranged by silicon in the air background, and the silicon dielectric column in the photonic crystal
  • the radius is 0.3006a ⁇ 0.3045a
  • the normalized frequency is (0.4103 ⁇ 0.4138)
  • the separation factor is (0.7712 ⁇ 0.7906)
  • the magneto-optical medium column length is (0.2801a ⁇ 0.2815a)
  • the center distance of the column is (1.3224a - 1.3365a) or (1.2807a - 1.3122a)
  • the insertion loss of the circulator is less than 0.05dB
  • the high refractive index dielectric material of the circulator is silicon
  • the low refractive index medium The material is air
  • the photonic crystal is formed by periodically arranging silicon in an air background.
  • the radius of the silicon dielectric column in the photonic crystal is 0.28a to 0.3344a, the normalized frequency is (0.4073 to 0.4160), and the separation factor is ( 0.7634 ⁇ 0.8056), the length of the magneto-optical medium column is (0.2745a ⁇ 0.2863a), the center distance of the corner dielectric column is (1.2488a ⁇ 1.3852a), the insertion loss of the circulator is less than 0.2dB; the high refractive index
  • the dielectric material is silicon, and the low refractive index dielectric material is air.
  • the photonic crystal is periodically arranged by silicon in an air background.
  • the radius of the silicon dielectric column in the photonic crystal is 0.2693a to 0.3671a, and the normalized frequency.
  • the ratio is (0.4043 to 0.4192), the separation factor is (0.7558 to 0.8208), the length of the magneto-optical medium column is (0.2686a to 0.2885a), and the center distance of the corner dielectric column is (1.2304a to 1.4764a). Insertion loss is less than 0.5 dB; the high refractive index dielectric material is silicon, the low The radioactive medium material is air, and the photonic crystal is formed by periodically arranging silicon in an air background. The radius of the silicon dielectric column in the photonic crystal is 0.2642a to 0.3818a, and the normalized frequency is (0.4016-0.4235).
  • the factor is (0.7473 ⁇ 0.8316), the length of the column of the magneto-optical medium is (0.2639a ⁇ 0.2922a), the center distance of the corner dielectric column is (1.2162a ⁇ 1.6971a), and the insertion loss of the circulator is less than 1dB.
  • the ultra-efficient compact cross-type circulator based on photonic crystal waveguide of the invention can be widely applied to microwave, terahertz and optical communication bands. Compared with the prior art, it has the following positive effects.
  • the invention can realize the loop of the signal through a ferrite rod in a short distance, which is convenient and efficient;
  • the invention can make electromagnetic waves circulate clockwise or counterclockwise by changing the polarity of the bias field
  • the present invention has a very low insertion loss at the output port and a very high isolation at the isolated port;
  • the principle of the present invention can apply the characteristics that the photonic crystal can be scaled without considering the dispersion or the dispersion, and the function of the electromagnetic wave in different bands can be realized by the method of changing the lattice constant in equal proportion.
  • FIG. 1 is a schematic view showing the structure of an ultra-efficient compact cross-type circulator based on a photonic crystal waveguide of the present invention and a coordinate system used in the present invention.
  • FIG. 2 is a photonic band gap diagram of a square dielectric column photonic crystal of the present invention and a TE band structure diagram corresponding to an optimized maximum photonic band gap.
  • Fig. 2(a) is a diagram showing the relationship between the band gap and the edge length s b of the background medium.
  • the forbidden band with a relative forbidden band ratio of 36% is obtained.
  • Fig. 3 is a structural diagram of the strip defect photonic crystal (i.e., photonic crystal waveguide) of the present invention, in which a conduction mode exists in the middle of the forbidden band.
  • the linear dispersion interval marked in Fig. 3 is selected by the condition d ⁇ /dk ⁇ (20% of the peak of d ⁇ /dk).
  • Figure 4 (a) is a two-dimensional diagram of the intensity of the odd-mode resonant mode field distribution of the ferrite rod of the present invention in the absence of a bias magnetic field, i.e., the ferrite rod is not magnetized, wherein the points are The color represents the electric field strength at each point.
  • Fig. 4(b) is a two-dimensional diagram of the intensity and other chromaticity of the even mode resonant mode field distribution in the case where the ferrite rod is not magnetized in the present invention, wherein the color of each point represents the electric field intensity at each point.
  • Figure 5 is a two-dimensional diagram of the resonant mode field distribution of the ferrite rod of the present invention in the case of a bias magnetic field, that is, the ferrite rod is magnetized (the electric field intensity and other chromaticity two-dimensional map, wherein the color of each point represents each The electric field strength of the point).
  • Fig. 5(a) is a spiral distribution diagram of the resonant mode field in the system in the case where the ferrite rod is magnetized.
  • Fig. 5(b) is an enlarged view of the central area of Fig. 5(a).
  • Fig. 6 is a diagram showing the distribution of the resonant mode field energy flow in the case where the ferrite rod of the present invention is magnetized.
  • Fig. 6(a) is a two-dimensional chromaticity diagram showing the intensity of the energy flow distribution, wherein the color of each point represents the energy flow intensity value of each point.
  • Fig. 6(b) is a three-dimensional chromaticity diagram of the intensity contour of the energy flow field distribution, wherein the color of each point represents the energy flow intensity value of each point, and the height of each point represents the energy flow intensity of each point.
  • FIG. 7 is a schematic structural view of a central region of an ultra-efficient compact cross-type circulator based on a photonic crystal waveguide according to the present invention.
  • Fig. 8 is a graph showing the insertion loss and the isolation of the ultra-efficient compact cross-type circulator based on the photonic crystal waveguide according to the present invention.
  • the characteristics of the insertion loss are in the frequency range of 0.2 dB or less.
  • FIG. 9 is a simulation result of field distribution and energy flow distribution of an ultra-efficient compact cross-type circulator based on a photonic crystal waveguide.
  • Fig. 9(a) is a two-dimensional chromaticity diagram showing the intensity of the field distribution, showing that the electromagnetic wave electric field is efficiently looped without any loss, wherein the color of each point represents the electric field intensity value of each point.
  • Fig. 9(b) is a two-dimensional chromaticity diagram showing the intensity of the energy flow distribution, showing that almost all of the energy is looped to the P2 port, wherein the color of each point represents the energy flow intensity value of each point.
  • 10(a), 10(b), 10(c), and 10(d) are chromaticity two-dimensional, such as the intensity of electric field distribution when electromagnetic waves are input from the four ports of the cross-type circulator of the present invention.
  • the figure in which the color of each point represents the electric field intensity value of each point.
  • Figure 11 (a) is an embodiment structural example, wherein a cylindrical background medium column corner is applied with four triangular columns;
  • Figure 11 (b) is an embodiment structural example, wherein a cylindrical background medium column corner is applied with four semi-circular columns;
  • Figure 11 (c) is an embodiment structural example, wherein a hexagonal background medium column corner is applied with four semi-hexagonal columns;
  • Figure 11 (d) is an embodiment structural example, wherein a hexagonal shaped background medium column corner is applied with four triangular columns;
  • Fig. 11(e) shows an embodiment example in which four semi-circular columns are applied to the corners of the hexagonal background medium column.
  • the ultra-efficient compact cross-type circulator based on photonic crystal waveguide of the present invention comprises a four-port cross-shaped photonic crystal waveguide; a square magneto-optical medium is placed at a center of a crisscross photonic crystal waveguide.
  • magneto-optical medium rod adopts ferrite or magneto-optical medium material
  • the cross section of the magneto-optical medium rod adopts square, rectangular, circular, elliptical, circular, pentagonal, hexagonal, arbitrary polygon, arbitrary Close the curve
  • four corner rods are respectively arranged at four corners of the center of the T-shaped cross-waveguide, and the four square dielectric rods are cut into the same angle as the other square poles (the background square dielectric rod).
  • the cross section of the four corner dielectric rods is triangular, semi-circular, semi-elliptical, semi-polygonal, or a closed pattern formed by straight edges and curves, and the corner dielectric rod coincides with the left side of its corresponding grid position Or not coincident;
  • the cross section of the background dielectric column of the photonic crystal cross-waveguide is triangular, circular, semi-circular, An elliptical, semi-elliptical, polygonal, or closed curve;
  • the photonic crystal is alternately arranged by a high refractive index medium and a low refractive index medium, and the photonic crystal is arranged by a high refractive index dielectric rod in a background of a low refractive index medium.
  • the input wave from any input end of the photonic crystal waveguide is looped clockwise or counterclockwise to an adjacent output waveguide port that is orthogonal to the input end waveguide by 90 degrees.
  • the direction of the electromagnetic wave is changed with the direction of the applied magnetic field.
  • the electromagnetic wave signal incident from the port 1 (P1) port will be looped efficiently and low-cost to the port 2 (P2) port; likewise, P2 to port 3 (P3), P3 to port 4 (P4) ), P4 to P1 can achieve the same loop effect.
  • the coordinate system in this description is shown in Figure 1.
  • a is a lattice constant
  • the material of the high refractive index dielectric rod is made of silicon
  • the refractive index in the microwave band can be considered as 3.4
  • the low refractive index medium is air.
  • a frequency sweep sequence with the length of the side of the dielectric rod as a variable can be set to study the distribution of the change of the side length with the forbidden band. As shown in Fig.
  • FEM Finite Element Method
  • the ferrite in the present invention is biased in the z-axis direction, in which case the relative permeability tensor is:
  • 4 is in the non-magnetized state can be obtained.
  • 4(a) and 4(b) are odd and even modes, respectively.
  • the magnetic permeability becomes the tensor form described above, and the ferrite is in a magnetized state.
  • the splitting coefficient is 0.77, a significant gyromagnetic effect can be observed, and the electric field shown in Fig. 5(a) exhibits a swirling distribution when the magneto-optical medium is in a magnetized state.
  • FIG. 5(b) it can be clearly seen that when the ferrite is magnetized, the resonance field exhibits a Tai Chi-like distribution.
  • the Poynting vector or energy flow distribution can be calculated:
  • Equation 9 E z is ⁇ and It is the amplitude and phase, and the * is a complex conjugate symbol.
  • Equation 9 The energy flow distribution map can be calculated by Equation 9, as shown in FIG. Since the electric field at the center point of the vortex field is zero, its energy flow density is also zero.
  • the present invention is in the area of the distribution center of the structure shown in Figure 7, the side length of the square background s b lattice constants a media column in a distributed throughout the device and perpendicular to one another to form the cross waveguide by deleting a row and column media
  • the width of the waveguide is: (2a-s b ).
  • the square rods located at the four corners of the intersection center are chamfered to become an isosceles right triangle having a right angle side and still s b as shown in FIG.
  • the four triangles have a variable distance d c with respect to the center point of the cross-waveguide. By changing this distance, the transmission effect of light at the corner can be optimized.
  • the square ferrite at the center of the waveguide is set to have a side length of s m . Since the electromagnetic wave coupling effect in the central region is very complicated, we define the electric field distribution factors affected by ferrite, triangular rod and waveguide, respectively. Similarly, for the magnetic field we define Thus, the electric and magnetic field distribution of the entire system can be written as:
  • the objective function to be examined is set by introducing the Nelder-Mead optimization method. Let the objective function based on the energy flow distribution have the following form:
  • f opt is a multivariate function controlled by ⁇ , p, s m and d c . Obviously, the smaller the value of f opt , the better the looping effect of the entire system. By calculation we can find the minimum value of this f opt , as follows:
  • Insertion loss and isolation are important indicators for examining the performance of a circulator. For the case of incident from P1, they are defined as follows:
  • InsertionLoss P1-P2 10log 10 (P 1 /P 2 )
  • Isolation P1-P4 10log 10 (P 1 /P 4 )
  • the frequency interval with an insertion loss of 0.2 dB is generally a working interval
  • FIG. 8 is a calculation of the insertion loss and isolation of the cross-shaped circulator of the present invention.
  • the operating frequency is 0.4121, that is, consistent with equation (13)
  • a minimum value of 0.02 dB insertion loss can be obtained, and the maximum values of isolation for the P3 and P4 ports are 46 dB and 48 dB, respectively.
  • the photonic crystal dielectric column radius is 0.3a
  • the normalized frequency is 0.4121
  • the separation factor is 0.7792
  • the magneto-optical medium column length is 0.2817a
  • the corner dielectric column center distance is 1.2997a, which can be obtained as shown in FIG. result.
  • 10(a), 10(b), 10(c), and 10(d) are chromaticity two-dimensionalities such as the intensity of electric field distribution when electromagnetic waves are input from the four ports of the cross-shaped circulator of the present invention, respectively.
  • FIG. 11 An ultra-efficient compact cross-type circulator based on a photonic crystal waveguide of the present invention is shown in Fig. 11 as an example of a circulator applying columns of other shapes having different shapes and purposes for the same purpose at four corners of a photonic crystal waveguide formed of columns of different shapes.
  • Embodiment 1 is a diagrammatic representation of Embodiment 1:
  • the photonic crystal dielectric column radius is 0.3a
  • the normalized frequency is 0.4121
  • the separation factor is 0.7792
  • the magneto-optical medium column length is 0.2817a
  • the corner dielectric column center distance is 1.2997a
  • the circulator insertion loss is 0.02. dB.
  • Embodiment 2 is a diagrammatic representation of Embodiment 1:
  • the photonic crystal dielectric column radius is 0.3a
  • the separation factor is 0.7792
  • the magneto-optical medium column length is 0.2817a
  • the corner dielectric column center distance is 1.2997a
  • the normalized frequencies are 0.4138, 0.4160, 0.4192, and 0.4235, respectively.
  • the insertion loss of the circulator is 0.05 dB, 0.2 dB, 0.5 dB, and 1 dB, respectively.
  • the normalized frequency is 0.4121
  • the photonic crystal dielectric column radius is 0.3a
  • the magneto-optical medium column side length is 0.2817a
  • the corner dielectric column center distance is 1.2997a
  • the separation factors are 0.7906, 0.8056, 0.8208, and 0.8316, respectively.
  • the insertion loss of the device is 0.05dB, 0.2dB, 0.5dB and 1dB respectively.
  • the normalized frequency is 0.4121
  • the radius of the photonic crystal dielectric column is 0.3a
  • the separation factor is 0.7792
  • the center distance of the corner dielectric column is 1.2997a
  • the side length of the magneto-optical medium column is 0.2815a, 0.2863a, 0.2885a and 0.2922a respectively.
  • the insertion loss of the circulator is 0.05 dB, 0.2 dB, 0.5 dB, and 1 dB, respectively.
  • Embodiment 5 is a diagrammatic representation of Embodiment 5:
  • the normalized frequency is 0.4121
  • the photonic crystal dielectric column radius is 0.3a
  • the separation factor is 0.7792
  • the magneto-optical medium column side length is 0.2817a
  • the corner dielectric column center distance d c is 1.3365a, 1.3852a, 1.4764a, respectively.
  • the insertion loss of the circulator is 0.05dB, 0.2dB, 0.5dB and 1dB, respectively.
  • Embodiment 6 is a diagrammatic representation of Embodiment 6
  • the same loop function as the previous example can be achieved by applying dielectric columns of different shapes and purposes to the four corners of the photonic crystal waveguide composed of different shaped dielectric columns.
  • four triangular prisms are applied at the corners of the cylindrical background dielectric column, and ferrite of the corresponding material is placed at the center, and the separation factor p is separated by controlling the operating frequency f as described in the above example.
  • the ferrite side length s m and the four corner triangle columns have a center distance d c to achieve high performance loop function.
  • different working intervals such as 0.05 dB, 0.2 dB, 0.5 dB, and 1 dB are set.
  • Embodiment 7 is a diagrammatic representation of Embodiment 7:
  • Fig. 11(b) As shown in Fig. 11(b), four semi-circular columns are applied at the corners of the cylindrical background dielectric column, and ferrite of the corresponding material is placed at the center, and separated by controlling the operating frequency f as described in the above example.
  • the coefficient p, the ferrite side length s m , and the four corner semi-cylindrical center distance d c are used to achieve the function of high performance loop.
  • different working intervals such as 0.05 dB, 0.2 dB, 0.5 dB, and 1 dB are set.
  • Embodiment 8 is a diagrammatic representation of Embodiment 8
  • ferrite of the corresponding material is placed at the center, by controlling the operating frequency f as described in the above example, Separation coefficient p, ferrite side length s m , four corners and half hexagonal column center distance d c to achieve high performance loop function.
  • different working intervals such as 0.05 dB, 0.2 dB, 0.5 dB, and 1 dB are set.
  • Embodiment 9 is a diagrammatic representation of Embodiment 9:
  • ferrite of the corresponding material is placed at the center, and the separation factor is controlled by controlling the operating frequency f as described in the above example.
  • Different working intervals such as 0.05 dB, 0.2 dB, 0.5 dB, and 1 dB are set based on the insertion loss curve associated with the above parameters.
  • Embodiment 10 is a diagrammatic representation of Embodiment 10:

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Nonlinear Science (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Optical Integrated Circuits (AREA)

Abstract

一种基于光子晶体波导的超高效紧凑十字型环行器，它包括一个四个端口的十字交叉的光子晶体波导；所述的十字交叉光子晶体波导中心放置一个方形磁光介质杆；位于交叉波导中心的四个拐角处，分别设置四个方形介质杆切角成为直角边与背景方形介质杆边长相同的等腰直角三角形以形成拐角介质杆；所述拐角介质杆与其对应格点位置的左边重合或不重合；所述环行器的插入损耗为0.02dB～1dB，其隔离端与输入端的隔离度大于14dB。该环行器结构体积小，集成度高，电磁波传输效率高，便于集成而且高效环行，可广泛应用于微波、太赫兹和光通信波段。

Description

基于光子晶体波导的超高效紧凑十字型环行器 技术领域
本发明涉及四端口十字型环行器领域,尤其涉及一种基于光子晶体技术的十字型环形行器。
背景技术
自从电磁学诞生以来，环行器以它独特的功能被广泛使用。环形器根据不同的用途可以应用于不同波段与器件。如当做隔离器使用时，可以通过屏蔽来自输出端的信号而使信号只能在一个方向上传播；而在雷达技术中，环形器可以将信号从发射器环行到天线、再从天线环行到接收器，而实现双工器的功能；在反射放大器中，环行器作为非互易器件可以将放大的输出信号与输入端分离。
近年来，随着光子晶体理论的提出，光子晶体波导被认为是可以高效传输电磁波的一种媒质。因此，光子晶体波导理论为探索高效率的微波集成电路和集成光路开拓了新的领域。在集成大量组件的微波器件和集成光路中，各个组件之间不可避免的会产生各种回波干扰而影响整个系统的功能。因此，将这些干扰最小化将是优化整个系统的首要任务。基于铁氧体材质的光子晶体波导环行器是一种非互易器件，它可以使波沿单一方向传播，而反向传播的波将被导入到另一波导。尽管目前已经设计出来的基于光子晶体波导的环行器相对于传统的磁光环行器来说，体积小了许多而且具有更好的性能，然而大部分设计都使用了多根磁光介质柱或耦合介质柱，并且与波前直接作用，因而结构还是相对复杂并且带宽相对较窄。
发明内容
本发明的目的是克服现有技术中的不足，提供一种基于光子晶体波导的超高效紧凑十字型环行器。
本发明的目的通过下述技术方案予以实现。
本发明的基于光子晶体波导的超高效紧凑十字型环行器包括一 个四个端口的十字交叉的光子晶体波导；所述的十字交叉光子晶体波导中心放置一个方形磁光介质杆；所述位于交叉波导中心的四个拐角处，分别设置四个方形介质杆切角成为直角边与背景方形介质杆边长相同的等腰直角三角形以形成拐角介质杆；所述拐角介质杆与其对应格点位置的左边重合或不重合；所述环行器的插入损耗为0.02dB～1dB，其隔离端与输入端的隔离度大于14dB。
所述光子晶体由高折射率介质杆在低折射率介质背景中周期排列而成，或由低折射率介质杆在高折射率介质背景中周期排列而成。
所述高折射率介质材料为硅、砷化镓、二氧化钛、氮化硅等折射率大于2的介质，低折射率介质材料为空气、真空、二氧化硅、冰晶石、橄榄油或折射率小于1.6的介质。
所述光子晶体波导的任意输入端输入的波沿顺时针或逆时针环行到相邻的与输入端波导90度正交的输出波导端口，电磁波的环行方向随外加磁场的方向而改变。
所述磁光介质杆为铁氧体材料。
所述磁光介质杆的横截面为方形、矩形、圆形、椭圆形、环行、五边形、六边形、任意多边形、任意闭合曲线。
所述四个拐角介质杆的横截面为三角形、半圆形、半椭圆形、半多边形、或由一直边和曲线形成的闭合图形。
所述光子晶体十字交叉波导的背景介质柱的横截面为三角形、圆形、半圆形、椭圆型、半椭圆形、多边形、或闭合曲线。
所述高折射率介质材料为硅，所述低折射率介质材料为空气，所述光子晶体由硅在空气背景周期排列而成，所述光子晶体中的硅介质柱半径为0.3a，归一化频率为0.4121、分离因子为0.7792、磁光介质柱边长为0.2817a、拐角介质柱中心距为1.2997a，所述环行器的插入损耗为0.02dB，其中a为光子晶体的晶格常数，分离因子为磁光介质的相对磁导率张量的第1行第2个量的绝对值与第1行第1个元素的值的比值，归一化频率为ωa/2πc，ω为圆频率，c为真空中光速；所述高折射率介质材料为硅，所述低折射率介质材料为空气，所述光子晶体由硅在空气背景周期排列而成，所述光子晶体中的硅介质柱半径为0.3006a～0.3045a，归一化频率为(0.4103～0.4138)、分离因子为(0.7712～0.7906)、磁光介质柱边长为(0.2801a～0.2815a)、拐角介质 柱中心距为(1.3224a～1.3365a)或(1.2807a～1.3122a)，所述环行器的插入损耗小于0.05dB；所述环行器的高折射率介质材料为硅，所述低折射率介质材料为空气，所述光子晶体由硅在空气背景周期排列而成，所述光子晶体中的硅介质柱半径为0.28a～0.3344a，归一化频率为(0.4073～0.4160)、分离因子为(0.7634～0.8056)、磁光介质柱边长为(0.2745a～0.2863a)、拐角介质柱中心距为(1.2488a～1.3852a)，所述环形器的插入损耗小于0.2dB；所述高折射率介质材料为硅，所述低折射率介质材料为空气，所述光子晶体由硅在空气背景周期排列而成，所述光子晶体中的硅介质柱半径为0.2693a～0.3671a，归一化频率为(0.4043～0.4192)、分离因子为(0.7558～0.8208)、磁光介质柱边长为(0.2686a～0.2885a)、拐角介质柱中心距为(1.2304a～1.4764a)，所述环形器的插入损耗小于0.5dB；所述高折射率介质材料为硅，所述低折射率介质材料为空气，所述光子晶体由硅在空气背景周期排列而成，所述光子晶体中的硅介质柱半径为0.2642a～0.3818a，归一化频率为(0.4016～0.4235)、分离因子为(0.7473～0.8316)、磁光介质柱边长为(0.2639a～0.2922a)、拐角介质柱中心距为(1.2162a～1.6971a)，所述环行器的插入损耗小于1dB。
本发明的基于光子晶体波导的超高效紧凑十字型环行器可广泛应用于微波、太赫兹和光通信波段。它与现有技术相比，具有如下积极效果。
1.结构体积小，集成度高，电磁波传输效率高，适合大规模集成；
2.本发明在短程通过一个铁氧体杆就可以实现信号的环行，便于集成而且高效；
3.本发明通过改变偏置场的极性，即可使电磁波沿顺时针或逆时针环行；
4.本发明在输出端口具有极低的插入损耗，而在隔离端口具有非常高的隔离度；
5.本发明原理在不考虑色散或色散可以忽略的情况下，可以应用光子晶体可等比例缩放的特性，通过等比例改变晶格常数的方法，可以实现在不同波段电磁波环行的功能。
附图说明
图1为本发明的基于光子晶体波导的超高效紧凑十字型环行器的结构示意图及本发明采用的坐标系。
图2为本发明的方形介质柱光子晶体的光子带隙图和优化最大光子带隙对应的TE带结构图。
图2(a)为带隙与背景介质柱边长sb的关系图，在背景介质柱边长为sb＝0.3a的情况下，具有相对禁带比为36％的禁带。
图2(b)为sb＝0.3a的情况下的带结构图。
图3为本发明中的线缺陷光子晶体(即光子晶体波导)的带结构图，在禁带中间存在一个传导模。而图3中所标的线性色散区间，是通过条件dω/dk<(dω/dk的峰值的20％)来选取的。
图4(a)为本发明的铁氧体杆在无偏置磁场情况下，即铁氧体杆未磁化情况下的奇模谐振模场分布的强度等色度二维图，其中各点的颜色代表各点的电场强度。
图4(b)为本发明的铁氧体杆未磁化情况下的偶模谐振模场分布的强度等色度二维图，其中各点的颜色代表各点的电场强度。
图5为本发明的铁氧体杆在有偏置磁场情况下，即铁氧体杆被磁化情况下的谐振模场分布图(电场强度等色度二维图，其中各点的颜色代表各点的电场强度)。
图5(a)为在铁氧体杆被磁化情况下，系统中谐振模场的漩涡状分布图。
图5(b)为图5(a)中心区域的放大图。
图6为本发明的铁氧体杆被磁化情况下的谐振模场能流分布图。
图6(a)为能流分布的强度等色度二维图，其中各点的颜色代表各点的能流强度值。
图6(b)为能流场分布的强度等高等色度三维图，其中各点的颜色代表各点的能流强度值，各点的高度表示各点的能流强度。
图7为本发明基于光子晶体波导的超高效紧凑十字型环行器中心区域的结构示意图。
图8为本发明基于光子晶体波导的超高效紧凑十字型环行器的插入损耗和隔离度随频率变化的特性，图中只给出了插入损耗为在0.2dB以下的频率区间内的特性。
图9为本发明基于光子晶体波导的超高效紧凑十字型环形器的场分布与能流分布模拟结果。
图9(a)为场分布的强度等色度二维图，显示电磁波电场无任何损耗地高效环行，其中各点的颜色代表各点的电场强度值。
图9(b)为能流分布的强度等色度二维图，显示能量几乎全部被环行到P2端口，其中各点的颜色代表各点的能流强度值。
图10(a)、图10(b)、图10(c)、图10(d)为电磁波分别从本发明的十字型环行器的四个端口输入时的电场分布的强度等色度二维图，其中各点的颜色代表各点的电场强度值。
图11(a)为一个实施结构例，其中圆柱形背景介质柱拐角施加有四个三角柱；
图11(b)为一个实施结构例，其中圆柱形背景介质柱拐角施加有四个半圆形柱；
图11(c)为一个实施结构例，其中六角形形背景介质柱拐角施加有四个半六角形柱；
图11(d)为一个实施结构例，其中六角形形背景介质柱拐角施加有四个三角形柱；
图11(e)为一个实施结构例，其中六角形形背景介质柱拐角施加有四个半圆形柱。
具体实施方式
如图1所示，本发明的基于光子晶体波导的超高效紧凑十字型环行器包括一个四个端口的十字交叉的光子晶体波导；在一个十字交叉的光子晶体波导中心位置放置一个方形磁光介质杆；磁光介质杆采用铁氧体或磁光介质材料；所述磁光介质杆的横截面采用方形、矩形、圆形、椭圆形、环行、五边形、六边形、任意多边形、任意闭合曲线；同时在T字交叉波导中心的四个角落分别设置四个拐角杆，将四个方形介质杆切角成为直角边与其他方形杆(背景方形介质杆)边长相同的等腰直角三角形以形成拐角介质杆；四个拐角介质杆的横截面采用三角形、半圆形、半椭圆形、半多边形、或由一直边和曲线形成的闭合图形，拐角介质杆与其对应格点位置的左边重合或不重合；光子晶体十字交叉波导的背景介质柱的横截面采用三角形、圆形、半圆形、 椭圆型、半椭圆形、多边形、或闭合曲线；所述光子晶体由高折射率介质和低折射率介质交替排列布置而成，光子晶体由高折射率介质杆在低折射率介质背景中排列形成的结构和由低折射率介质杆在高折射率介质背景中排列形成的结构。光子晶体波导的任意输入端输入的波沿顺时针或逆时针环行到相邻的与输入端波导90度正交的输出波导端口，电磁波波的环行方向随外加磁场的方向而改变。
图1中所示，从端口1(P1)端口入射的电磁波信号将被高效低耗地环行到端口2(P2)端口中去；同样，P2至端口3(P3)、P3至端口4(P4)、P4至P1都可以实现同样的环行效果。本说明中的坐标系如图1中所示。
首先，我们选择以正方晶格分布的方形介质杆阵列作为背景光子晶体。其中a为晶格常数，高折射率介质杆的材质采用硅(Silicon)，其在微波波段的折射率可以认为是3.4，低折射率介质为空气。为了得到最宽的光子晶体完全禁带，可以设置一个以介质杆边长为自变量的频率扫描序列，来研究边长变化随禁带的分布情况。如图2(a)中所示，通过使用有限元方法(Finite Element Method，缩写为FEM)方法并计算场中的特征频率，可以得到在背景介质柱边长为sb＝0.3a的情况下，具有相对禁带比为36％的禁带。针对这个禁带，图2(b)中详细的带结构图。
在微波集成电路和光集成器件中，避免不同频率引起的群速度不同是至关重要的，直接影响着信号的质量。为了最小化不同频率信号造成的群速色散，找出d2ω/dk2＝0的区间是必要的。在光子晶体线缺陷波导中，带结构的投射图如图3中所示，在禁带中间存在一个传导模。图3所展示的即为此导模上的线性区间，此线性区间是通过取dω/dk的峰值的20％来界定的。本说明中所计算出的此线性区间的归一化频率范围为：
f＝(2πc)-1ωa＝a/λ＝0.3748～0.4511
(1)
在本说明以下阐述的实施过程中，都以此频率范围为基础进行研究。
如图1中所示，本发明中的铁氧体按z轴方向偏置，在此情况下，相对磁导率张量为：
Figure PCTCN2015085345-appb-000001
其中p为归一化磁化率或分离因子：
Figure PCTCN2015085345-appb-000002
当κ/μ增加时，根据偏置磁场方向的不同，会产生两个不同的谐振频率ωn +和ωn -，其中一个是沿顺时针方向ejnφ传播，一个是按逆时针方向e-jnφ传播，这也是p被称作分离因子的原因。对于一个被p磁化的电磁场，麦克斯韦方程组可以表示为：
Figure PCTCN2015085345-appb-000003
Figure PCTCN2015085345-appb-000004
Figure PCTCN2015085345-appb-000005
Figure PCTCN2015085345-appb-000006
由式(4)-(7)可以得到如下方程：
Figure PCTCN2015085345-appb-000007
其中k2＝ω2ε0μ0ε(μ2-κ2)/μ＝ω2ε0μ0εμe为有效波数的平方，ε＝12.9是铁氧体材料的相对介电常数，μe＝(μ2-κ2)/μ是有效相对磁导率，ε0和μ0为真空中的介电常数和磁导率。如果铁氧体没有被磁化，即外加磁场为0，此时κ＝0，μe＝μ。通过使用FEM法计算式(8)中的场，可以得到如图4中所示的铁氧体处于非磁化状态下的两个谐振模式。其中图4(a)和图4(b)分别是奇模和偶模。当在系统中引入偏置场后，磁导率变为上面所述的张量形式，铁氧体处于磁化状态。当分裂系数为0.77时，可以观察到明显的旋磁效应，如图5(a)所展示的电场在磁光介质处于磁化状态下呈现漩涡状分布。而在放大的图5(b)中，可以明显看到这种由铁氧体磁化时，谐振场呈现太极状分布。根据电场可以计算出坡印廷矢量或能流分布：
Figure PCTCN2015085345-appb-000008
其中Ez为
Figure PCTCN2015085345-appb-000009
ρ和
Figure PCTCN2015085345-appb-000010
是幅值与相位，*号为复数共轭符号。由式9可以计算出能流分布图，如图6所示。由于涡旋场中心点的电场为0，其能流密度也为0。
本发明在中心区域的结构分布如图7中所示，边长为sb方形介质柱以晶格常数a分布于整个器件的背景，并通过删除一行和一列介质柱而形成互相垂直的十字波导，波导的宽度为：(2a-sb)。同时，对位于交叉中心四个角落处的方形杆进行切角操作，使其成为如图7中所示的直角边长仍为sb的等腰直角三角形。另外，这四个三角形相对于交叉波导中心点有一个可以变动的距离dc，通过改变这个距离，可以 优化光在拐弯处的传输效果。最后，设定位于波导中心处的方形铁氧体的边长为sm。由于在中心区域的电磁波耦合效应是非常复杂的，因此我们定义受铁氧体、三角形杆和波导影响的电场分布因子分别为
Figure PCTCN2015085345-appb-000011
同样地，对于磁场我们定义
Figure PCTCN2015085345-appb-000012
这样，整个系统的电场和磁场分布可以写成：
Figure PCTCN2015085345-appb-000013
Figure PCTCN2015085345-appb-000014
为简洁起见，同时因为本说明中的十字环形器相对于中心是90°对称的，我们在这里先只研究电磁波信号从P1输入，环行到P2输出而同时隔离P3、P4的情况，从其他端口输入的情况应与目前这种情况是完全相同的。通过引入Nelder-Mead优化方法，来设置所需要考察的目标函数。设基于能流分布的目标函数有以下形式：
Figure PCTCN2015085345-appb-000015
其中fopt是由ω,p,sm和dc控制的多元函数。显而易见，fopt的值越小，整个系统的环行效果越好。通过计算我们可以找到这个fopt的最小值，详细如下：
fopt|min(f＝0.4121,p＝0.7792,sm＝0.2817a,dc＝1.2997a)＝3.8489e-5.
(13)
插入损耗和隔离度是考察一个环行器性能的重要指标，对于从P1入射的情况，它们的定义如下：
InsertionLossP1-P2＝10log10(P1/P2)
(14)
IsolationP1-P3＝10log10(P1/P3)
(15)
IsolationP1-P4＝10log10(P1/P4)
(16)
其中P1,P2,P3和P4是各个端口处的均时功率流。我们设定范围为方程(1)的频率f为自变量，来考察上述插入损耗与隔离度。
由于本发明是获得一个高性能的四端口环行器，因此一般将插入损耗为0.2dB的频率区间为工作区间，图8为通过计算得出的本发明的十字型环形器的插入损耗和隔离度在该频率区间内随频率变化的特性。如图8中所示，我们可以看到所有的隔离度都大于14dB。另外，当工作频率为0.4121，即与方程(13)一致时，可以获得一个插入损耗为0.02dB的最小值，同时对应P3、P4端口的隔离度的最大值分别为46dB与48dB。
采用光子晶体介质柱半径为0.3a、归一化频率为0.4121、分离因子为0.7792、磁光介质柱边长为0.2817a、拐角介质柱中心距为1.2997a，可得到如图9中所描述的结果。从图9(a)中可以观察到，从P1入射的电磁波电场几乎没有任何损耗地环行到P2端口；从图9(b)中可以观察到，由于电磁波被高效地环行，能流自然而然非常好地被环行到P2端口。因此，整个器件可以实现如图10所示的效果。图10(a)、图10(b)、图10(c)、图10(d)为电磁波分别从本发明的十字型环形器的四个端口输入时的电场分布的强度等色度二维 图，它显示了波在环形器中的环行效果。可见本发明是一种基于光子晶体波导的超高效紧凑十字型环行器。
如图11所示本发明基于光子晶体波导的超高效紧凑十字型环行器通过在不同形状介质柱构成的光子晶体波导的四个角落处施加形状不同、目的相同的其它形状柱子的环形器实例。
实施方案1：
采用光子晶体介质柱半径为0.3a、归一化频率为0.4121、分离因子为0.7792、磁光介质柱边长为0.2817a、拐角介质柱中心距为1.2997a，所述环行器的插入损耗为0.02dB。
实施方案2：
采用光子晶体介质柱半径为0.3a、分离因子为0.7792、磁光介质柱边长为0.2817a、拐角介质柱中心距为1.2997a，归一化频率分别取为0.4138、0.4160、0.4192和0.4235，则环行器的插损分别为0.05dB、0.2dB、0.5dB和1dB。
实施方案3：
采用归一化频率为0.4121、光子晶体介质柱半径为0.3a、磁光介质柱边长为0.2817a、拐角介质柱中心距为1.2997a，分离因子分别取0.7906、0.8056、0.8208和0.8316，则环行器的插损分别为0.05dB、0.2dB、0.5dB和1dB。
实施方案4：
采用归一化频率为0.4121、光子晶体介质柱半径为0.3a、分离因子为0.7792、拐角介质柱中心距为1.2997a，磁光介质柱边长分别取0.2815a、0.2863a、0.2885a和0.2922a，则环行器的插损分别为0.05dB、0.2dB、0.5dB和1dB。
实施方案5：
采用归一化频率为0.4121、光子晶体介质柱半径为0.3a、分离因子为0.7792、磁光介质柱边长为0.2817a，拐角介质柱中心距dc 分别取为1.3365a、1.3852a、1.4764a和1.6971a，则环行器的插损分别为0.05dB、0.2dB、0.5dB和1dB。
实施方案6：
通过在不同形状介质柱构成的光子晶体波导的四个角落处施加形状不同、目的相同的介质柱，都可以实现与之前实例相同的环行功能。如图11(a)，所示，在圆柱形背景介质柱角落施加四个三角柱，并在中心处放置相应材质的铁氧体，通过控制如上述实例所述的工作频率f,分离系数p，铁氧体边长sm，四个拐角三角柱中心距离dc来实现高性能环行的功能。根据考察与上述参数相关的插入损耗曲线，来设定如0.05dB、0.2dB、0.5dB、1dB等不同的工作区间。
实施方案7：
如图11(b)，所示，在圆柱形背景介质柱角落施加四个半圆形柱，并在中心处放置相应材质的铁氧体，通过控制如上述实例所述的工作频率f,分离系数p，铁氧体边长sm，四个拐角半圆柱中心距离dc来实现高性能环行的功能。根据考察与上述参数相关的插入损耗曲线，来设定如0.05dB、0.2dB、0.5dB、1dB等不同的工作区间。
实施方案8：
如图11(c)，所示，在六角形形背景介质柱角落施加四个半六角形柱，并在中心处放置相应材质的铁氧体，通过控制如上述实例所述的工作频率f,分离系数p，铁氧体边长sm，四个拐角半六角形柱中心距离dc来实现高性能环行的功能。根据考察与上述参数相关的插入损耗曲线，来设定如0.05dB、0.2dB、0.5dB、1dB等不同的工作区间。
实施方案9：
如图11(d)，所示，在六角形形背景介质柱角落施加四个三角形柱，并在中心处放置相应材质的铁氧体，通过控制如上述实例所述的工作频率f,分离系数p，铁氧体边长sm，四个拐角三角形柱中心距离dc来实现高性能环行的功能。根据考察与上述参数相关的插入损 耗曲线，来设定如0.05dB、0.2dB、0.5dB、1dB等不同的工作区间。
实施方案10：
如图11(e)，所示，在六角形形背景介质柱角落施加四个半圆形柱，并在中心处放置相应材质的铁氧体，通过控制如上述实例所述的工作频率f,分离系数p，铁氧体边长sm，四个拐角半圆形柱中心距离dc来实现高性能环行的功能。根据考察与上述参数相关的插入损耗曲线，来设定如0.05dB、0.2dB、0.5dB、1dB等不同的工作区间。
由于本发明所提供的配置方法是基于归一化频率的，因此对于不同的波段，可以通过公式
Figure PCTCN2015085345-appb-000016
来设计在相应的频率下符合要求的光子晶体波导的超高效超紧凑十字型环形器。
以上所述本发明在具体实施方式及应用范围均有改进之处，不应当理解为对本发明限制。

Claims (9)

  1. 一种基于光子晶体波导的超高效紧凑十字型环行器，其特征在于：其包括一个四个端口的十字交叉的光子晶体波导；所述的十字交叉光子晶体波导中心放置一个方形磁光介质杆；所述位于交叉波导中心的四个拐角处，分别设置四个方形介质杆切角成为直角边与背景方形介质杆边长相同的等腰直角三角形以形成拐角介质杆；所述拐角介质杆与其对应格点位置的左边重合或不重合；所述环行器的插入损耗为0.02dB～1dB，其隔离端与输入端的隔离度大于14dB。
  2. 按照权利要求1所述的基于光子晶体波导的超高效紧凑十字型环行器，其特征在于：所述光子晶体由高折射率介质杆在低折射率介质背景周期排列而成，或由低折射率介质杆在高折射率介质背景中周期排列而成。
  3. 按照权利要求2所述的基于光子晶体波导的超高效紧凑十字型环行器，其特征在于：所述高折射率介质材料为硅、砷化镓、二氧化钛、氮化硅或折射率大于2的介质，低折射率介质材料为空气、真空、二氧化硅、冰晶石、橄榄油或折射率小于1.6的介质。
  4. 按照权利要求1所述的基于光子晶体波导的超高效紧凑十字型环行器，其特征在于：所述光子晶体波导的任意输入端输入的波沿顺时针或逆时针环行到相邻的与输入端波导90度正交的输出波导端口，波的环行方向随外加磁场的方向而改变。
  5. 按照权利要求1所述的基于光子晶体波导的超高效紧凑十字型环行器，其特征在于：所述磁光介质杆为铁氧体材料。
  6. 按照权利要求1或7所述的基于光子晶体波导的超高效紧凑十字型环行器，其特征在于：所述磁光介质杆的横截面为方形、矩形、圆形、椭圆形、环行、五边形、六边形、任意多边形、任意闭合曲线。
  7. 按照权利要求1所述的基于光子晶体波导的超高效紧凑十字型环行器，其特征在于：所述四个拐角介质杆的横截面为三角形、半圆形、半椭圆形、半多边形、或由一直边和曲线形成的闭合图形。
  8. 按照权利要求1所述的基于光子晶体波导的超高效紧凑十字型环行器，其特征在于：所述光子晶体十字交叉波导的背景介质柱的横截面为三角形、圆形、半圆形、椭圆型、半椭圆形、多边形、或闭合曲线。
  9. 按照权利要求3所述的基于光子晶体波导的超高效紧凑十字型环行器，其特征在于：所述高折射率介质材料为硅，所述低折射率介质材料为空气，所述光子晶体由硅在空气背景周期排列而成，所述光子晶体中的硅介质柱半径为0.3a，归一化频率为0.4121、分离因子为0.7792、磁光介质柱边长为0.2817a、拐角介质柱中心距为1.2997a，所述环行器的插入损耗为0.02dB，其中a为光子晶体的晶格常数，分离因子为磁光介质的磁导率张量的第1行第2个量的绝对值与第1行第1个元素的值比值，归一化频率为ωa/2πc，ω为圆频率，c为真空中光速；
    所述高折射率介质材料为硅，所述低折射率介质材料为空气，所述光子晶体由硅在空气背景周期排列而成，所述光子晶体中的硅介质柱半径为0.3006a～0.3045a，归一化频率为(0.4103～0.4138)、分离因子为(0.7712～0.7906)、磁光介质柱边长为(0.2801a～0.2815a)、拐角介质柱中心距为(1.3224a～1.3365a)或(1.2807a～1.3122a)，所述环行器的插入损耗小于0.05dB；
    所述高折射率介质材料为硅，所述低折射率介质材料为空气，所述光子晶体由硅在空气背景周期排列而成，所述光子晶体中的硅介质柱半径为0.28a～0.3344a，归一化频率为(0.4073～0.4160)、分离因子为(0.7634～0.8056)、磁光介质柱边长为(0.2745a～0.2863a)、拐角介质柱中心距为(1.2488a～1.3852a)，所述环行器的插入损耗小于0.2dB；
    所述高折射率介质材料为硅，所述低折射率介质材料为空气，所述光子晶体由硅在空气背景周期排列而成，所述光子晶体中的硅介质柱半径为0.2693a～0.3671a，归一化频率为(0.4043～0.4192)、分离因子为(0.7558～0.8208)、磁光介质柱边长为(0.2686a～0.2885a)、拐角介质柱中心距为(1.2304a～1.4764a)，所述环行器的插入损耗小于0.5dB；
    所述高折射率介质材料为硅，所述低折射率介质材料为空气，所述光子晶体由硅在空气背景周期排列而成，所述光子晶体中的硅介质柱半径为0.2642a～0.3818a，归一化频率为(0.4016～0.4235)、分离因子为(0.7473～0.8316)、磁光介质柱边长为(0.2639a～0.2922a)、拐角介质柱中心距为(1.2162a～1.6971a)，所述环行器的插入损耗小于1dB。
PCT/CN2015/085345 2014-07-28 2015-07-28 基于光子晶体波导的超高效紧凑十字型环行器 Ceased WO2016015629A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201410363260.5A CN104101948B (zh) 2014-07-28 2014-07-28 基于光子晶体波导的十字型环行器
CN201410363260.5 2014-07-28

Publications (1)

Publication Number Publication Date
WO2016015629A1 true WO2016015629A1 (zh) 2016-02-04

Family

ID=51670232

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2015/085345 Ceased WO2016015629A1 (zh) 2014-07-28 2015-07-28 基于光子晶体波导的超高效紧凑十字型环行器

Country Status (2)

Country Link
CN (1) CN104101948B (zh)
WO (1) WO2016015629A1 (zh)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104101947B (zh) * 2014-07-28 2017-07-04 欧阳征标 基于光子晶体波导的超高效紧凑t字型环行器
CN104101948B (zh) * 2014-07-28 2017-04-12 欧阳征标 基于光子晶体波导的十字型环行器
BR102015010964A2 (pt) * 2015-04-29 2016-11-01 Univ Fed Do Pará circulador t baseado em um cristal fotônico bidimensional com rede quadrada
CN105070996B (zh) * 2015-07-29 2018-09-14 常熟浙瑞亘光电技术有限公司 基于磁等离子激元单向腔的四端口太赫兹波环行器
CN105607305B (zh) * 2016-02-15 2021-03-02 欧阳征标 基于光子晶体t型波导的横向输出磁光调制器
CN105572918B (zh) * 2016-02-15 2021-02-19 深圳大学 基于光子晶体十字波导的磁控二选一光路开关
CN105572920B (zh) * 2016-02-15 2021-02-19 深圳大学 基于光子晶体十字波导的双路反相光学时钟信号发生器
CN105607303B (zh) * 2016-02-15 2021-02-19 深圳大学 基于光子晶体t型波导的直角输出磁光调制器
CN105572919B (zh) * 2016-02-15 2021-02-19 深圳大学 基于光子晶体十字波导的磁光调制器
CN105572921B (zh) * 2016-02-15 2021-02-19 深圳大学 基于光子晶体t型波导的磁控二选一直角输出光路开关

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080267557A1 (en) * 2005-12-29 2008-10-30 Zheng Wang Integrated Magneto-Optical Devices for Uni-Directional Optical Resonator Systems
CN101726873A (zh) * 2009-12-14 2010-06-09 深圳大学 光子晶体三端口环行器
CN101788727A (zh) * 2009-12-14 2010-07-28 深圳大学 基于磁光腔耦合的光子晶体四端口环行器
CN102043261A (zh) * 2010-08-31 2011-05-04 深圳大学 光子晶体磁光环行器及其制备方法
CN104101948A (zh) * 2014-07-28 2014-10-15 欧阳征标 基于光子晶体波导的超高效紧凑十字型环行器

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006184618A (ja) * 2004-12-28 2006-07-13 Kyoto Univ ２次元フォトニック結晶及びそれを用いた光機能素子
CN102707462A (zh) * 2012-06-12 2012-10-03 中国科学院半导体研究所 基于磁光光子晶体的4×4二进制发生器

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080267557A1 (en) * 2005-12-29 2008-10-30 Zheng Wang Integrated Magneto-Optical Devices for Uni-Directional Optical Resonator Systems
CN101726873A (zh) * 2009-12-14 2010-06-09 深圳大学 光子晶体三端口环行器
CN101788727A (zh) * 2009-12-14 2010-07-28 深圳大学 基于磁光腔耦合的光子晶体四端口环行器
CN102043261A (zh) * 2010-08-31 2011-05-04 深圳大学 光子晶体磁光环行器及其制备方法
CN104101948A (zh) * 2014-07-28 2014-10-15 欧阳征标 基于光子晶体波导的超高效紧凑十字型环行器

Also Published As

Publication number Publication date
CN104101948A (zh) 2014-10-15
CN104101948B (zh) 2017-04-12

Similar Documents

Publication Publication Date Title
CN104101947B (zh) 基于光子晶体波导的超高效紧凑t字型环行器
CN104101948B (zh) 基于光子晶体波导的十字型环行器
CN104570409B (zh) 一种紧凑型六端口光子晶体环行器
CN104597631B (zh) 一种引入三角引导柱的宽频带三端口光环行器
CN106681027B (zh) 基于磁性光子晶体的单向慢光缺陷波导结构及非互易器件
Wang et al. T-shaped optical circulator based on coupled magneto-optical rods and a side-coupled cavity in a square-lattice photonic crystal
Wang et al. Low-loss Y-junction two-dimensional magneto-photonic crystals circulator using a ferrite cylinder
CN107908021A (zh) 基于光子晶体波导的t字型光子晶体环行器
Zhang et al. Design of nonreciprocal waveguide devices based on two-dimensional magneto-optical photonic crystals
CN115566384A (zh) 一种基于拓扑手性边界态的高效电磁波导
CN104597630B (zh) 一种引入补偿柱的高传输率和高隔离度的三端口光环行器
Danaie et al. Design of adjustable T-shaped and Y-shaped photonic crystal power splitters for TM and TE polarizations
CN104767020B (zh) 一种自旋波定向传输波导结构
Umamaheswari et al. Exploration of photonic crystal circulator based on gyromagnetic properties and scaling of ferrite materials
CN108646443A (zh) 三端口光子晶体环行器
CN109471275A (zh) 一种三端口光子晶体环行器
CN103645541A (zh) 一种太赫兹偏振分束器
Xu et al. Characterization of millimeter wave photonic crystal circulator with a ferrite sphere
Wang et al. Transmission-reflection decoupling of non-Hermitian photonic doping epsilon-near-zero media
CN106025462A (zh) 基于人工表面等离激元和互补开口谐振环的带阻滤波器
Xu et al. Magnetic photonic crystal circulator based on gradient changing width waveguide
Zhang et al. One-way rotating photonic crystal ring resonator with high quality factor
CN106154416A (zh) 无泄漏低损磁光薄膜磁表面快模可控单向任意拐弯波导
Wang et al. Ultra-wideband terahertz circulator with a ferrite-sphere filled triangle photonic crystal
CN103529519A (zh) 一种基于非互易微环耦合器的光学隔离器

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 15827295

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 15827295

Country of ref document: EP

Kind code of ref document: A1