CN215264109U

CN215264109U - Two-dimensional photonic crystal waveguide structure

Info

Publication number: CN215264109U
Application number: CN202120698381.0U
Authority: CN
Inventors: 蒋雨霄
Original assignee: Jiangsu University
Current assignee: Jiangsu University
Priority date: 2021-04-07
Filing date: 2021-04-07
Publication date: 2021-12-21
Anticipated expiration: 2031-04-07

Abstract

The utility model provides a two dimension photonic crystal waveguide structure is equipped with a pair of linear waveguide in photonic crystal, is equipped with regular hexagon's the chamber that encloses between two linear waveguide, and linear waveguide is the same with the waveguide width who encloses the chamber, and the limit that encloses the chamber and be close to linear waveguide is parallel with linear waveguide, encloses the chamber and can set up one or more, and perpendicular to linear waveguide arranges when wherein setting up a plurality of. The coupler is formed by the enclosing cavity, so that the two-dimensional photonic crystal waveguide structure of the utility model has a coupling characteristic; when the light wave incident from the linear waveguide on one side meets a specific frequency, the coupling action is triggered, and then the light wave is reversely emitted from the linear waveguide on the other side. The utility model discloses waveguide structure's coupling characteristic can be arranged in the optical communication field to realize filtering function, also perhaps is applied to the optical circulator field.

Description

Two-dimensional photonic crystal waveguide structure

Technical Field

The utility model belongs to the optics field, concretely relates to two-dimentional photonic crystal waveguide structure.

Background

The photonic crystal is an artificial material with a periodic structure, is formed by periodically arranging materials with different refractive indexes in space, and can form a waveguide through introducing line defects therein due to the characteristic of photonic band gap, and further form a geometric waveguide loop on the basis of the waveguide loop, so that the movement of photons therein can be controlled, and the purpose of controlling a light wave transmission path in a low-loss mode is achieved.

Compared with the transmission technology based on electrons in the traditional communication field, photons have higher transmission speed and larger information capacity, no interaction exists among the photons, and the integration level is higher, so that the optical device formed based on the photon transmission characteristic has the advantages of small volume, easiness in large-scale integration, high efficiency and the like. Meanwhile, due to a topological insulator (a material which is insulated as a whole but conductive on the surface and propagates unidirectionally) similar to the quantum hall effect and the quantum spin hall effect which are generated by deep research in recent years, the photonic crystal promotes the development of an optical communication technology by virtue of the most basic characteristic of a photonic band gap.

Based on the above situation, in order to further improve the application of photonic crystals in the field of optical communication, further research and study on the structure and characteristics of photonic crystal waveguides are needed.

SUMMERY OF THE UTILITY MODEL

In view of this, the present invention provides a two-dimensional photonic crystal waveguide structure, which is used to provide a structural model of two-dimensional photonic crystal coupling characteristic and transmission characteristic that has more visual effect under the condition of no external magnetic field.

The utility model discloses a following technical means realizes above-mentioned technical purpose.

A two-dimensional photonic crystal waveguide structure is provided, wherein a pair of linear waveguides is arranged in a photonic crystal, and an enclosure cavity is arranged between the two linear waveguides.

Furthermore, the photonic crystal is formed by periodically arranging two kinds of dielectric columns in an air background, and three adjacent dielectric columns in each kind of dielectric column are arranged in a regular triangle.

Further, the media columns are classified into mediocre media columns and topological media columns; radius of mediocre medium column

The distance between every two is a; the radius R2 of the topological medium column is a/6.24, the distance between every two topological medium columns is a/2, wherein a is a lattice constant; the two dielectric columns are made of silicon.

Further, the enclosure cavity is a regular hexagon; two sides of the enclosure cavity close to the linear waveguides on the two sides are parallel to the linear waveguides.

Further, the straight waveguide and the enclosed cavity are both made by introducing line defects between the two dielectric columns, and the waveguide widths of the straight waveguide and the enclosed cavity are equal.

Further, the waveguide widths of the straight line waveguide and the enclosed cavity are equal, and the waveguide widths

Furthermore, the number of the enclosed cavities between the two linear waveguides is one, and two rows of topological state medium columns are arranged between the enclosed cavities and the linear waveguides on the two sides.

Furthermore, the number of the enclosing cavities between the two linear waveguides is multiple, and the enclosing cavities are arranged perpendicular to the linear waveguides.

Furthermore, the number of the enclosing cavities is two, and three rows of topological state medium columns are arranged between the two enclosing cavities.

Further, the side length of the regular hexagon at the inner side of the enclosure cavity

The utility model has the advantages that:

(1) the utility model provides a novel two-dimensional photonic crystal waveguide structure, wherein an enclosure cavity is arranged between two parallel linear waveguides, and a coupler is formed by the enclosure cavity, so that the two-dimensional photonic crystal waveguide structure of the utility model has a coupling characteristic; when the light wave incident from the linear waveguide on one side meets a specific frequency, the coupling action is triggered, and then the light wave is reversely emitted from the linear waveguide on the other side. The utility model discloses waveguide structure's coupling characteristic can be arranged in the optical communication field to realize filtering function, or be applied to the optical circulator field.

(2) The utility model discloses among the waveguide structure, adopting regular hexagon's the chamber that encloses, comparing in other for example circular chamber that encloses, the structure is more directly perceived, and scanning process and corresponding operation are more convenient.

(3) The regular hexagon enclosed cavities in the waveguide structure of the utility model can be arranged in a plurality and are arranged perpendicular to the linear waveguide; setting up a plurality of surrounding cavities can not change holistic coupling characteristic, but for taking the utility model discloses waveguide structure provides convenience for the waveguide access of more complicated huge structure of foundation structure.

Drawings

FIG. 1 is a two-dimensional photonic crystal waveguide structure diagram of the present invention;

FIG. 2 is a diagram showing the results of the optical wave coupling test of the two-dimensional photonic crystal waveguide structure of the present invention;

FIG. 3 is a diagram showing another set of coupling test results of the waveguide structure of the present invention;

fig. 4 is the utility model discloses a coupling test result chart when two enclose the chamber.

Reference numerals:

11-mediocre medium column; 12-a topological dielectric column; 21-a linear waveguide; 22-surrounding cavity.

Detailed Description

Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present invention, and should not be construed as limiting the present invention.

The two-dimensional photonic crystal waveguide structure diagram of the present invention is shown in fig. 1, wherein the photonic crystal comprises two different dielectric columns, the two dielectric columns are periodically arranged in the air background, and in each of the dielectric columns, a regular triangle is arranged between the three adjacent dielectric columns. The great circle in the figure shows a mediocre medium column 11, the radius of which

The small circle in the figure shows a topological medium column 12, and the radius R2 is a/6.24; the distance between each two mediumcolumns 11 (namely, the distance between two adjacent large circles in the figure) D1 is a, and the distance between each two topologic medium columns 12 (namely, the distance between two adjacent small circles in the figure) D2 is a/2, wherein a is a lattice constant; the two dielectric columns are made of silicon materials, the dielectric constant of the silicon materials is 11.7, and the dielectric constant of the air background is 1. The refractive indexes of the two dielectric cylinders are different, and at the junction of the two dielectric cylinders, a plurality of dielectric cylinders are eliminatedThe dielectric rods, i.e., the method of introducing line defects, can be formed into waveguides.

The two-dimensional photonic crystal waveguide structure shown in fig. 1 includes two parallel linear waveguides 21, a regular hexagonal enclosure cavity 22 is disposed between the two linear waveguides 21, and two sides of the regular hexagonal enclosure cavity 22 close to the two linear waveguides 21 are parallel to the linear waveguides 21; the linear waveguide 21 and the cavity 22 are both made by the method for introducing line defects between two dielectric columns, and the waveguide widths of the two are equal, the waveguide width will affect the position of the boundary mode line (i.e. the connecting line of the light spots in fig. 2-4), and the boundary mode line is optimally just in the middle of the band gap, and this embodiment gives a preferable waveguide width through continuous optimization simulation

The side length of the regular hexagon at the inner side of the enclosure cavity 22

Two rows of topological state medium columns 12 are arranged between the surrounding cavity 22 and the linear waveguides 21 on two sides.

The cavities 22 between the straight waveguides 21 form waveguide couplers, and due to the geometric property of the regular hexagon of the cavities 22, the peripheries of the graphs are all curved waveguides with 60 degrees, and simulation tests show that the frequency f of the light waves is (1.5713 × e)¹⁴Hz，1.5729*e¹⁴Hz), a strong coupling phenomenon occurs, and the test results are shown in fig. 2: the incident light source is arranged at point P in the straight waveguide 21 at the upper left corner of the figure, and the brighter spot reflects the propagation path of the optical wave. As shown in fig. 2, the light wave is incident into the upper linear waveguide 21 from the point P, and propagates to the right in a single direction strictly in the waveguide direction, and when passing through the hexagonal enclosure 22, the light wave is coupled, and then is transmitted into the lower linear waveguide 21 through the enclosure 22, and finally exits in the lower linear waveguide 21 in the direction opposite to the incident direction. The whole process from the injection to the injection of the light wave in the trigger coupling operation satisfies the one-way propagation characteristic, specifically, after the light wave is coupled from the left half section of the upper linear waveguide 21 into the enclosure 22, no residual light wave is left and continues to followThe right half of the upper waveguide 21 is emitted; after the light waves are coupled into the lower linear waveguide 21 from the surrounding cavity 22, all the light waves are emitted leftwards through the left half section of the lower waveguide, and the light waves are not emitted from the left direction and the right direction simultaneously.

In addition to the frequencies of the lightwaves found in the above experiments, the lightwave frequency f was also found to be (1.6129 × e)¹⁴Hz，1.6161*e¹⁴Hz), similar coupling characteristics are also triggered, the results of which are shown in fig. 3; likewise, in addition to the two frequency ranges found in the above example, there are other light wave frequencies that can trigger the coupling characteristic, which are not listed here. Through the above-mentioned experiment proves, the utility model discloses two-dimensional photonic crystal waveguide structure under the condition of no any external magnetic field, just can make the light wave of specific frequency trigger the coupling effect of enclosing chamber 22 as the coupler in the waveguide structure to the light wave transmission direction that this specific frequency must be changed to the low loss. The characteristic can realize the filtering function in the field of optical communication; or in the field of optical circulators.

As shown in fig. 4, in the present embodiment, two regular hexagonal cavities 22 are disposed between two linear waveguides 21, the size of the two cavities 22 is the same as that in the previous experiment, and the two cavities 22 are arranged perpendicular to the linear waveguides 21, and three rows of topological dielectric pillars 12 are spaced between the two cavities. Also as in the previous experiments, a light source is provided in the linear waveguide 21 in the upper left corner of the figure, and light waves are coupled into the linear waveguide 21 below through the double-walled cavity 22 and then emitted in the opposite direction. Proved by the above test, the utility model discloses in the two-dimensional photonic crystal waveguide structure, can set up between the linear waveguide 21 of two parallels that a plurality of perpendicular to linear waveguide 21 arrange enclose chamber 22, and set up a plurality ofly enclose chamber 22 and set up singly to enclose chamber 22 coupling characteristic the same.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplification of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. The present invention is not limited to the above embodiments, and any obvious improvements, replacements or modifications that can be made by those skilled in the art without departing from the essence of the present invention belong to the protection scope of the present invention.

Claims

1. A two-dimensional photonic crystal waveguide structure, characterized by: a pair of parallel linear waveguides (21) is arranged in the photonic crystal, and an enclosure cavity (22) is arranged between the two linear waveguides (21); the photonic crystal is formed by periodically arranging two medium columns in an air background, and three adjacent medium columns in each medium column are arranged in a regular triangle; the medium columns comprise a mediocre medium column (11) and a topological medium column (12); radius of mediocre medium column (11)

The distance D1 between the two mediocre medium columns (11) is a; the radius R2 of the topological medium columns (12) is a/6.24, and the distance D2 between the two topological medium columns (12) is a/2, wherein a is a lattice constant; the two dielectric columns are made of silicon.

2. The two-dimensional photonic crystal waveguide structure of claim 1, wherein: the surrounding cavity (22) is in a regular hexagon shape; two sides of the surrounding cavity (22) close to the linear waveguides (21) on two sides are parallel to the linear waveguides (21).

3. The two-dimensional photonic crystal waveguide structure of claim 2, wherein: the linear waveguide (21) and the enclosure (22) are both made by introducing line defects between two dielectric columns.

4. A two-dimensional photonic crystal waveguide structure according to claim 3, wherein: the waveguide widths of the linear waveguide (21) and the enclosed cavity (22) are equal, and the waveguide widths

5. The two-dimensional photonic crystal waveguide structure of claim 2, wherein: the number of the surrounding cavities (22) between the two linear waveguides (21) is one, and two rows of topological state medium columns (12) are arranged between the surrounding cavities (22) and the linear waveguides (21) on two sides.

6. The two-dimensional photonic crystal waveguide structure of claim 2, wherein: the number of the enclosed cavities (22) between the two linear waveguides (21) is a plurality, and the enclosed cavities are arranged perpendicular to the linear waveguides (21).

7. The two-dimensional photonic crystal waveguide structure of claim 6, wherein: the number of the surrounding cavities (22) is two, and three rows of topological state medium columns (12) are arranged between the two surrounding cavities.

8. The two-dimensional photonic crystal waveguide structure of claim 2, wherein: the side length of the regular hexagon at the inner side of the enclosure cavity (22)