CN216434437U - Wavelength selection all-optical switch based on surface plasmon polaritons - Google Patents

Abstract

The invention relates to a wavelength selection all-optical switch based on surface plasmon polariton, belonging to the technical field of micro-nano photoelectron; the wavelength selection all-optical switch consists of a substrate layer and a rectangular metal layer, wherein the rectangular metal layer is tightly attached to the upper side of the substrate layer, a first straight waveguide, a second straight waveguide, a third straight waveguide, a fourth straight waveguide and an equilateral triangle resonant cavity which are as high as the rectangular metal layer are etched on the rectangular metal layer, the directions of the second straight waveguide and the fourth straight waveguide are the same as the long side direction of the rectangular metal layer, and the included angles between the first straight waveguide and the third straight waveguide and the long side direction of the rectangular metal layer are both 60 degrees; a rectangular metal block which has the same height as the rectangular metal layer and the center of which is coincided with the inner center of the equilateral triangle resonant cavity is also arranged in the equilateral triangle resonant cavity; the wavelength selection all-optical switch based on the surface plasmon has the advantages of simple structure, selectable wavelength and high extinction ratio, and can be applied to large-scale integrated optical communication devices in the future.

Description

Wavelength-selective all-optical switch based on surface plasmon

technical field

The wavelength-selective all-optical switch based on the surface plasmon polariton of the invention belongs to the technical field of micro-nano optoelectronics.

Background technique

Surface plasmon is an electromagnetic evanescent wave that propagates along the interface between metal and dielectric and decays exponentially in the vertical direction of the interface. The electromagnetic wave has the properties of breaking the traditional diffraction limit and electric field confinement.

As a typical waveguide structure based on surface plasmon filter, metal-dielectric-metal structure has the characteristics of high light confinement and easy fabrication. Therefore, surface plasmon-based metal-dielectric-metal structure has been applied in different photonic components, such as sensors, Mach-Zehnder interferometers, filters, etc.

In high-speed optical communication systems, optical switches are used as key node devices to realize functions such as optical cross-connect, optical switching, optical add-drop multiplexing, and network self-healing protection. At present, with the development of highly integrated all-off devices, the demand for all-optical switches to resist electromagnetic interference and fast response becomes more and more obvious. However, most of the existing all-optical switches are used to switch single-wavelength optical signals, and the wavelength cannot be It is particularly important to choose a multi-channel optical switch with complex structure and low extinction ratio, realizing wavelength selection, simple structure and high extinction ratio.

SUMMARY OF THE INVENTION

In order to achieve the above purpose, the present invention discloses a wavelength-selective all-optical switch based on surface plasmon polaritons. The all-optical switch realizes wavelength selectivity by entering different straight waveguides, with simple structure and high extinction ratio.

The object of the present invention is achieved in this way:

The wavelength selective all-optical switch based on surface plasmon is composed of a base layer and a rectangular metal layer. The straight waveguide, the second straight waveguide, the third straight waveguide, the fourth straight waveguide and the equilateral triangular resonant cavity, wherein the second straight waveguide and the fourth straight waveguide are in the same direction as the long sides of the rectangular metal layer, and the first straight waveguide and the fourth straight waveguide are in the same direction as the long sides of the rectangular metal layer. The angle between the three-straight waveguide and the longitudinal direction of the rectangular metal layer is 60°; in the equilateral triangular resonator cavity, a rectangular metal block having the same height as the rectangular metal layer and the center of the equilateral triangular resonant cavity coincident is also arranged.

The above-mentioned wavelength-selective all-optical switch based on surface plasmon polaritons has the following dimensions:

The size of the rectangular metal layer is 1160nm×530nm×75nm;

The width of the first straight waveguide is 50 nm, and the distance from the equilateral triangular resonator is d ₁ =18 nm;

The width of the second straight waveguide is 50nm, and the distance from the equilateral triangular resonator is d ₂ =20nm～50nm;

The width of the third straight waveguide is 50 nm, and the distance from the equilateral triangular resonator is d ₃ =18 nm;

The width of the fourth straight waveguide is 50 nm, and the distance from the equilateral triangular resonator is d ₄ =10 nm˜40 nm;

The side length of the equilateral triangular resonator is 484 nm;

The length h=200nm of the rectangular metal block, and the width w=20nm˜50nm.

Further, the base layer is made of silicon dioxide material, the rectangular metal layer and the rectangular metal block are made of silver material, the first straight waveguide, the second straight waveguide, the third straight waveguide, the fourth straight waveguide and so on. The side-triangular resonator is in communication with the air.

Beneficial effects:

First, the wavelength-selective all-optical switch of the present invention based on surface plasmon polaritons only includes three solid structures: a base layer, a rectangular metal layer, and a rectangular metal block, as well as a first straight waveguide, a second straight waveguide, and a third straight waveguide. Compared with other all-optical switches, it has the technical advantage of simple structure.

Second, the present invention is based on a wavelength-selective all-optical switch based on surface plasmon polaritons, which can switch and modulate optical signals of different wavelengths by incident in different straight waveguides. Compared with other all-optical switches, it has wavelength-selective Technical advantages.

Third, the present invention is based on the wavelength-selective all-optical switch of surface plasmon polaritons, and the highest extinction ratio can reach 11.7dB, which has the technical advantage of high extinction ratio compared with other all-optical switches.

Fourth, the wavelength-selective all-optical switch based on the surface plasmon polariton of the present invention can be applied to large-scale integrated optical communication devices in the future due to its simple structure, selectable wavelength and high extinction ratio.

Description of drawings

FIG. 1 is a schematic structural diagram of a wavelength selective all-optical switch based on surface plasmon polaritons according to the present invention.

FIG. 2 is a transmittance curve when the distance d ₂ between the second straight waveguide and the equilateral triangular resonator varies.

FIG. 3 is a transmittance curve when the distance d ₄ between the fourth straight waveguide and the equilateral triangular resonator varies.

FIG. 4 is the transmittance curve of the width w of the rectangular metal block.

Fig. 5 is the transmittance curve when the optical signal is input from different straight waveguides.

In the figure: 1 base layer, 2 rectangular metal layer, 3 first straight waveguide, 4 second straight waveguide, 5 third straight waveguide, 6 fourth straight waveguide, 7 equilateral triangular resonator, 8 rectangular metal blocks.

Detailed ways

The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

Specific implementation one

The wavelength-selective all-optical switch based on surface plasmon in this specific embodiment has a schematic structural diagram as shown in FIG. Above, the first straight waveguide 3 , the second straight waveguide 4 , the third straight waveguide 5 , the fourth straight waveguide 6 and the equilateral triangular resonator 7 with the same height as the rectangular metal layer 2 are etched on the rectangular metal layer 2 , wherein , the second straight waveguide 4 and the fourth straight waveguide 6 are in the same direction as the long side of the rectangular metal layer 2, and the included angles between the first straight waveguide 3 and the third straight waveguide 5 and the long side direction of the rectangular metal layer 2 are both 60° (Fig. α and β in 1 are both 60°); in the equilateral triangular resonant cavity 7, a rectangular metal block 8 is also provided with the same height as the rectangular metal layer 2 and the center coincides with the inner core of the equilateral triangular resonant cavity 7.

Specific embodiment two

The wavelength-selective all-optical switch based on surface plasmon in this specific embodiment is further defined on the basis of the specific embodiment 1:

The size of the rectangular metal layer 2 is 1160nm×530nm×75nm;

The width of the first straight waveguide 3 is 50 nm, and the distance from the equilateral triangular resonator 7 is d ₁ =18 nm;

The width of the second straight waveguide 4 is 50 nm, and the distance from the equilateral triangular resonator 7 is d ₂ =20 nm˜50 nm;

The width of the third straight waveguide 5 is 50 nm, and the distance from the equilateral triangular resonator 7 is d ₃ =18 nm;

The width of the fourth straight waveguide 6 is 50 nm, and the distance from the equilateral triangular resonator 7 is d ₄ =10 nm˜40 nm;

The side length of the equilateral triangular resonator 7 is 484 nm;

The length h=200nm and the width w=20nm˜50nm of the rectangular metal block 8 .

Specific embodiment three

The wavelength selective all-optical switch based on surface plasmon in this specific embodiment is further defined on the basis of the specific embodiment 1 or the specific embodiment 2: the base layer 1 is a silicon dioxide material, the rectangular The metal layer 2 and the rectangular metal block 8 are made of silver material, and the first straight waveguide 3 , the second straight waveguide 4 , the third straight waveguide 5 , the fourth straight waveguide 6 and the equilateral triangular resonant cavity 7 communicate with the air.

Specific embodiment four

For the wavelength-selective all-optical switch based on surface plasmon in this specific embodiment, a simulation test is carried out on the distance between the second straight waveguide 4 and the equilateral triangular resonator 7 being d ₂ respectively. When the distance d ₂ changes from 50 nm to 20nm, the transmittance curve is shown in Figure 2. It can be seen that in the range of 400nm to 700nm, with the decrease of _d2 , the transmittance of the two resonance peaks increases, and a slight red shift appears at the same time, and the waveform basically remains unchanged. Change.

Specific implementation five

For the wavelength-selective all-optical switch based on surface plasmon in this specific embodiment, a simulation test is performed on the distance between the fourth straight waveguide 6 and the equilateral triangular resonator 7 as d ₄ respectively. When the distance d ₄ changes from 40 nm to 10nm, the transmittance curve is shown in Figure 3. It can be seen that in the range of 400nm to 700nm, with the decrease of _d4 , the transmittance of the two resonance peaks increases, and a slight red shift appears at the same time, and the waveform basically remains unchanged. Change.

Specific embodiment six

For the wavelength-selective all-optical switch based on surface plasmon in this specific embodiment, the width w of the rectangular metal block 8 is simulated and tested. When the width w changes from 50 nm to 20 nm, the transmittance curve is shown in FIG. 4 . It can be seen that in the range of 400nm to 700nm, with the decrease of w, the transmittance of resonance peak 1 increases, the transmittance of resonance peak 2 is basically unchanged, and at the same time, there is a blue shift, and the waveform basically remains unchanged.

Specific embodiment seven

The wavelength-selective all-optical switch based on surface plasmon in this specific embodiment performs optical signal input to the first straight waveguide 3, the second straight waveguide 4, and the third straight waveguide 5, and the combination is as follows:

Combination 1. Input the second straight waveguide 4 separately;

Combination 2: Input the second straight waveguide 4 and the first straight waveguide 3 at the same time;

Combination 3: Input the second straight waveguide 4 and the third straight waveguide 5 at the same time;

Combination 4: Input the second straight waveguide 4, the first straight waveguide 3 and the third straight waveguide 5 at the same time;

The change of the transmittance curve is shown in Figure 5. It can be seen that in the range of 400nm to 550nm, the combination of four will make the extinction ratio of the first combination to the resonance peak 1 reach 4.5dB, and the combination of two and three will make the combination of one. The extinction ratio of resonant peak 2 reaches 11.7dB, which verifies the technical advantage of high extinction ratio compared to other all-optical switches.

Claims (3)

1. The wavelength selection all-optical switch based on surface plasmon is characterized by comprising a substrate layer (1) and a rectangular metal layer (2), wherein the rectangular metal layer (2) is tightly attached to the upper side of the substrate layer (1), a first straight waveguide (3), a second straight waveguide (4), a third straight waveguide (5), a fourth straight waveguide (6) and an equilateral triangle resonant cavity (7) which are as high as the rectangular metal layer (2) are etched on the rectangular metal layer (2), wherein the second straight waveguide (4) and the fourth straight waveguide (6) are the same as the long side direction of the rectangular metal layer (2), and the included angles between the first straight waveguide (3) and the rectangular metal layer (2) and the included angles between the third straight waveguide (5) and the long side direction of the rectangular metal layer (2) are both 60 degrees; a rectangular metal block (8) which has the same height with the rectangular metal layer (2) and the center of which is superposed with the inner center of the equilateral triangle resonant cavity (7) is also arranged in the equilateral triangle resonant cavity (7).

2. The surface plasmon based wavelength selective all-optical switch of claim 1, wherein the dimensions are defined as follows:

the size of the rectangular metal layer (2) is 1160nm multiplied by 530nm multiplied by 75 nm;

the width of the first straight waveguide (3) is 50nm, and the distance between the first straight waveguide and the equilateral triangle resonant cavity (7) is d₁＝18nm；

The width of the second straight waveguide (4) is 50nm, and the distance between the second straight waveguide and the equilateral triangle resonant cavity (7) is d₂＝20nm～50nm；

The width of the third straight waveguide (5) is 50nm, and the distance between the third straight waveguide and the equilateral triangle resonant cavity (7) is d₃＝18nm；

The width of the fourth straight waveguide (6) is 50nm, and the distance between the fourth straight waveguide and the equilateral triangle resonant cavity (7) is d₄＝10nm～40nm；

The side length of the equilateral triangle resonant cavity (7) is 484 nm;

the rectangular metal block (8) has a length h of 200nm and a width w of 20-50 nm.

3. Surface plasmon based wavelength selective all-optical switch according to claim 1 or 2, characterized in that the first (3), second (4), third (5), fourth (6) and equilateral triangular cavities (7) are in communication with air.

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