CN113904120A - Focused Terahertz Polarization Controller - Google Patents
Focused Terahertz Polarization Controller Download PDFInfo
- Publication number
- CN113904120A CN113904120A CN202111179781.1A CN202111179781A CN113904120A CN 113904120 A CN113904120 A CN 113904120A CN 202111179781 A CN202111179781 A CN 202111179781A CN 113904120 A CN113904120 A CN 113904120A
- Authority
- CN
- China
- Prior art keywords
- microstructure
- axis
- terahertz
- concave metal
- metal
- 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.)
- Pending
Links
- 230000010287 polarization Effects 0.000 title claims abstract description 52
- 239000002184 metal Substances 0.000 claims abstract description 91
- 229910052751 metal Inorganic materials 0.000 claims abstract description 91
- 239000004642 Polyimide Substances 0.000 claims abstract description 8
- 229920001721 polyimide Polymers 0.000 claims abstract description 8
- 239000000463 material Substances 0.000 claims description 9
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 8
- 239000010931 gold Substances 0.000 claims description 8
- 229910052737 gold Inorganic materials 0.000 claims description 8
- 238000004891 communication Methods 0.000 abstract description 4
- 238000012545 processing Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 17
- 230000033228 biological regulation Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 239000006096 absorbing agent Substances 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000009659 non-destructive testing Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
- H01Q15/0006—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices
- H01Q15/0086—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices said selective devices having materials with a synthesized negative refractive index, e.g. metamaterials or left-handed materials
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Polarising Elements (AREA)
Abstract
The invention discloses a focusing terahertz polarization controller. The terahertz wave polarization device is characterized by comprising a terahertz wave incidence end, a reflected terahertz wave output end and a super-surface polarizer; the super-surface polarizer is formed by periodically arranging N multiplied by N structural units on a plane vertical to the input direction of the terahertz wave, wherein N is a natural number; the array unit is obtained by rotating a 4 × 4 notched concave metal microstructure counterclockwise by a step of α =22.5 °; the notched concave metal microstructure comprises a metal notched concave part on the top layer, a polyimide dielectric layer on the middle layer and a metal plate on the bottom layer from top to bottom in sequence. The focusing terahertz polarization controller disclosed by the invention has the characteristics of simple structure, easiness in processing and the like, can generate different focus directions for the incidence of terahertz waves in different polarization states, and meets the application requirements of a terahertz wave communication multiplexing system.
Description
Technical Field
The invention relates to the field of terahertz waves, in particular to a focusing terahertz polarization controller.
Background
The terahertz wave is an electromagnetic wave with the frequency of 0.1-1.0 THz, is located between microwave and infrared in an electromagnetic spectrum, corresponds to a transition region from a macroscopic classical theory to a microscopic quantum theory and from the field of electronics to the field of photonics, and is a classical leading edge cross discipline. The terahertz band has been considered as a forbidden region in the electromagnetic spectrum for a considerable period of time. The segment of terahertz has been referred to as the "terahertz gap" and has not received much attention in the scientific community due to the lack of radiation sources and detectors that efficiently generate and detect terahertz waves. In recent years, with the rapid development of terahertz sources and detectors and the continuous research and development of terahertz functional devices, terahertz scientific technology has been developed vigorously, and the research on the terahertz scientific technology has a very wide application prospect in multiple fields such as nondestructive testing, safety inspection, biomedical imaging, radar, ultra-wideband communication and the like.
The development of the terahertz technology needs not only an efficient terahertz wave source and a high-sensitivity detector, but also a high-performance terahertz modulator, a wave absorber, a filter and other related functional devices. The terahertz wave polarization device is one of core devices of a terahertz system and is an important functional device capable of effectively regulating and controlling and changing the polarization state of terahertz waves. Conventional terahertz wave polarizers are often implemented using birefringence effects such as liquid crystals in crystals or polymers. However, the material only has birefringence at certain fixed frequency points, so that the terahertz wave is polarized only at a single frequency point, which greatly limits the application range of the polarization device, and the method for searching for the polarization control of the more efficient terahertz wave becomes very important.
The focusing terahertz polarization controller provided by the invention can be used for carrying out focusing regulation and control on terahertz waves in different polarization states, has the characteristics of simple structure, easiness in processing and the like, can generate different focus directions for incidence of terahertz waves in different polarization states, and meets the application requirements of a terahertz wave communication multiplexing system.
Disclosure of Invention
The invention provides a focusing terahertz polarization controller for overcoming the defects of the prior art.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a focusing terahertz polarization controller. The terahertz wave polarization device is characterized by comprising a terahertz wave incidence end, a reflected terahertz wave output end and a super-surface polarizer; the super-surface polarizer is formed by periodically arranging N multiplied by N structural units on a plane vertical to the input direction of the terahertz wave, wherein N is a natural number; the array unit is obtained by rotating a 4 × 4 notched concave metal microstructure counterclockwise by a step of α =22.5 °; the notched concave metal microstructure comprises a metal notched concave part on the top layer, a polyimide dielectric layer on the middle layer and a metal plate on the bottom layer from top to bottom in sequence.
The 16 microstructures in the structural unit are named as A-P in sequence. The concave metal microstructure with the notch in the microstructure A forms an angle of 22.5 degrees with the x axis; the concave metal microstructure with the notch in the microstructure B forms an angle of 45 degrees with the x axis; the notched concave metal microstructure in microstructure C was 67.5 degrees from the x-axis; the concave metal microstructure with the notch in the microstructure D forms an angle of 90 degrees with the x axis; the notched concave metal microstructure in microstructure E is at 112.5 degrees to the x-axis; the concave metal microstructure with the notch in the microstructure F forms 135 degrees with the x axis; the concave metal microstructure with the notch in the microstructure G forms 157.5 degrees with the x axis; the concave metal microstructure with the notch in the microstructure H forms an angle of 180 degrees with the x axis; the microstructure I and the x axis of the concave metal microstructure with the notch form an angle of 202.5 degrees; the concave metal microstructure with a notch in the microstructure J forms an angle of 225 degrees with the x axis; the notched concave metal microstructure in microstructure K was 247.5 ° from the x-axis; the concave metal microstructure with the notch in the microstructure L forms an angle of 270 degrees with the x axis; the concave metal microstructure with the notch in the microstructure M forms 292.5 degrees with the x axis; the concave metal microstructure with the notch in the microstructure N forms 315 degrees with the x axis; the concave metal microstructure with the notch in the microstructure O forms 337.5 degrees with the x axis; the notched concave metal microstructure in microstructure P is 0 ° to the x-axis.
The specific parameters of each part in the scheme can adopt the following preferable modes:
preferably, the structural unit consists of 16 notched concave metal microstructures, and the 16 microstructures are obtained by rotating counterclockwise by taking the angle alpha =22.5 degrees between the notch of the concave metal microstructure and the x axis as a step length.
Preferably, the concave metal microstructures with notches are arranged in an S shape.
Preferably, the concave side length of the metal notch of the top layer is 40-50 microns, the line width is 2-8 microns, the width of the left side concave part is 10-20 microns, the height is 5-15 microns, the width of the right side opening is 10-20 microns, the thickness is 0.2-1.0 microns, and the material is gold.
Preferably, the thickness of the polyimide dielectric layer is 35-45 μm.
Preferably, the thickness of the bottom layer metal plate is 0.2-1.0 μm, and the material is gold.
The focusing terahertz polarization controller has the characteristics of simple structure, easiness in processing and the like, can generate different focus directions for incidence of terahertz waves in different polarization states, and meets the application requirements of a terahertz wave communication multiplexing system.
Drawings
FIG. 1 is a schematic diagram of a three-dimensional structure, a unit structure and a concave metal microstructure with a notch of a focusing terahertz polarization controller arranged in an S shape;
FIG. 2 is a cross-sectional view of a notched concave metal microstructure element;
FIG. 3 is a schematic diagram of polarization control of an incident terahertz wave by a focusing terahertz polarization controller under incidence of different polarized waves;
fig. 4 is a focal point position and energy distribution diagram on an xy plane at a position z =900 μm directly above a focusing terahertz polarization controller when a left circularly polarized terahertz wave is incident.
Fig. 5 is an energy distribution diagram on an xz plane at a position z =900 μm right above a focusing terahertz polarization controller under incidence of a left circularly polarized terahertz wave.
Fig. 6 is a focal point position and energy distribution diagram on an xy plane at a position z =900 μm directly above a focusing terahertz polarization controller when a right circularly polarized terahertz wave is incident.
Fig. 7 is an energy distribution diagram on an xz plane at a position z =900 μm right above a focusing terahertz polarization controller under incidence of a right circularly polarized terahertz wave.
Fig. 8 is a diagram of two focus positions and energy distribution diagrams on an xy plane at a position z =900 μm directly above a focusing terahertz polarization controller under incidence of a linearly polarized terahertz wave.
Fig. 9 is an energy distribution diagram on an xz plane at a position z =900 μm right above a focusing terahertz polarization controller under incidence of a linearly polarized terahertz wave.
Fig. 10 is a schematic diagram of a 3 × 3 arrangement of notched concave metal microstructures rotated counterclockwise with a =40 ᵒ step size.
Fig. 11 is a diagram of the position of a focal point and an energy distribution in an xy plane at a position z =900 μm directly above the structure of fig. 9 when a left circularly polarized terahertz wave is incident.
Fig. 12 is a diagram of the distribution of the focal position and energy in the xy plane at z =900 μm directly above the structure of fig. 9 when a right circularly polarized terahertz wave is incident.
Detailed Description
Fig. 1 is a schematic diagram showing a three-dimensional structure, a unit structure and an S-shaped arrangement of a concave metal microstructure with a notch of a focusing terahertz polarization controller. Fig. 2 is a cross-sectional view of a notched concave metal microstructure element. Fig. 3 is a schematic diagram of polarization control of an incident terahertz wave by a focusing terahertz polarization controller under incidence of different polarized waves. The focusing terahertz polarization controller comprises a terahertz wave incidence end 1, a reflected terahertz wave output end 2 and a super-surface polarizer 3; the super-surface polarizer 3 is formed by arranging N multiplied by N structural units 4 on a plane vertical to the input direction of the terahertz wave periodically, wherein N is a natural number; the array unit 4 is obtained by rotating a 4 × 4 notched concave metal microstructure 5 counterclockwise by a step of α =22.5 °; the notched concave metal microstructure 5 sequentially comprises a metal notched concave part 6 on the top layer, a polyimide dielectric layer 7 on the middle layer and a metal plate 8 on the bottom layer from top to bottom.
In the focusing terahertz polarization controller, the materials and parameters of each component can be as follows:
the 16 microstructures in the structural unit 4 are named as A-P in sequence. The notched concave metal microstructure 5 in microstructure A makes an angle of 22.5 degrees with the x-axis; the notched concave metal microstructure 5 in microstructure B makes an angle of 45 degrees with the x-axis; the notched concave metal microstructure 5 in microstructure C is 67.5 ° from the x-axis; the notched concave metal microstructure 5 in microstructure D is at 90 degrees to the x-axis; the notched concave metal microstructure 5 in microstructure E makes an angle of 112.5 ° with the x-axis; the concave metal microstructure 5 with the notch in the microstructure F forms 135 degrees with the x axis; the notched concave metal microstructure 5 in microstructure G makes 157.5 ° with the x-axis; the concave metal microstructure 5 with a notch in the microstructure H forms an angle of 180 degrees with the x axis; the microstructure I and the concave metal microstructure 5 with the notch form an angle of 202.5 degrees with the x axis; the notched concave metal microstructure 5 in microstructure J makes 225 ° with the x-axis; the notched concave metal microstructure 5 in microstructure K was 247.5 ° from the x-axis; the notched concave metal microstructure 5 in the microstructure L makes an angle of 270 degrees with the x-axis; the concave metal microstructure 5 with the notch in the microstructure M forms 292.5 degrees with the x axis; the concave metal microstructure 5 with the notch in the microstructure N forms 315 degrees with the x axis; the concave metal microstructure 5 with the notch in the microstructure O forms an angle of 337.5 degrees with the x axis; the notched concave metal microstructure 5 in microstructure P is at 0 ° to the x-axis.
The structural unit 4 is composed of 16 concave metal microstructures 5 with notches, and the 16 microstructures are obtained by rotating anticlockwise by taking the angle alpha =22.5 degrees between the notch of the concave metal microstructure and the x axis as a step length. The concave metal microstructures 5 with the notches are arranged in an S shape. The concave 6 side length of the metal notch of the top layer is 40-50 microns, the line width is 2-8 microns, the width of the left side concave part is 10-20 microns, the height is 5-15 microns, the width of the right side opening is 10-20 microns, the thickness is 0.2-1.0 microns, and the material is gold. The thickness of the polyimide dielectric layer 7 is 35-45 mu m. The thickness of the bottom layer metal plate 8 is 0.2-1.0 mu m, and the material is gold.
Specific technical effects of the focusing terahertz polarization controller are explained by embodiments below.
Example 1
In this embodiment, the structure and the shapes of the components of the focusing terahertz polarization controller are as described above, and therefore are not described in detail. However, the specific parameters of each component are as follows:
the structural unit 4 is composed of 16 notched concave metal microstructures 5, and the 16 microstructures are obtained by rotating counterclockwise by taking the angle alpha =22.5 degrees between the notch of the concave metal microstructure and the x axis as a step length. The notched concave metal microstructures 5 are arranged in an "S" shape. The concave 6 side length of the metal notch on the top layer is 50 μm, the line width is 5 μm, the width of the concave part on the left side is 20 μm, the height is 10 μm, the width of the opening on the right side is 10 μm, the thickness is 1.0 μm, and the material is gold. The thickness of the polyimide dielectric layer 7 is 40 μm. The thickness of the bottom layer metal plate 8 is 0.2 μm, and the material is gold.
Terahertz wave signals are input from an input end 1 and output from a reflection terahertz wave output end 2 under the action of a focusing terahertz polarization controller. When a left circularly polarized terahertz wave is incident from the input end 1, a terahertz wave with the frequency of 1THz is reflected by the super-surface polarizer 3 and is output from the reflected terahertz wave output end 2, and a focus appears on the positive half axis of the x axis on the xy plane at a position z =900 μm directly above the focusing terahertz polarization controller and is 300 μm away from the zero point, as shown in fig. 4. Fig. 5 is an energy distribution diagram on an xz plane at a position z =900 μm right above a focusing terahertz polarization controller under incidence of a left circularly polarized terahertz wave, and a focus can be seen on the right side of the xz plane. When right circularly polarized terahertz waves are incident from the input end 1, terahertz waves with the frequency of 1THz are reflected by the super-surface polarizer 3 and output from the reflected terahertz wave output end 2, and a focus appears on the negative half axis of the x axis on the xy plane at z =900 μm just above the super-surface polarizer 3, which is 300 μm away from the zero point, as shown in fig. 6. Fig. 7 is an energy distribution diagram on an xz plane at a position z =900 μm right above a focusing terahertz polarization controller under incidence of right circularly polarized terahertz waves, and a focus can be seen on the left side of the xz plane. When a linearly polarized terahertz wave having a frequency of 1THz is incident, the reflected terahertz wave is output from the reflected terahertz wave output terminal 2, and two focal points are formed on both sides of the x-axis zero point on the xy plane at a distance of 600 μm at a position z =900 μm directly above the super surface polarizer 3, as shown in fig. 8. Fig. 9 is an energy distribution diagram on an xz plane at a position z =900 μm directly above a focusing terahertz polarization controller under incidence of a linearly polarized terahertz wave, and two focal points are respectively seen on the left side and the right side of the xz plane. As can be seen from fig. 4 to 9, when terahertz waves with different polarizations are incident, the positions of the focal points generated by the reflected terahertz waves are different after the terahertz waves are acted by the focusing terahertz polarization controller of the present invention, which indicates that the device can perform focusing regulation on terahertz waves with different polarization states.
Example 2
In this embodiment, the structural unit 4 of the focusing terahertz polarization controller is composed of 3 × 3 notched concave metal microstructures 5, where the notched concave metal microstructures 5 are obtained by rotating counterclockwise with α =40 ° as a step length, as shown in fig. 10. Terahertz wave signals are input from an input end 1 and output from a reflection terahertz wave output end 2 under the action of a focusing terahertz polarization controller. When a left circularly polarized terahertz wave is incident from the input terminal 1, a terahertz wave with a frequency of 1THz is reflected by the super surface polarizer 3 and output from the reflected terahertz wave output terminal 2, and at z =900 μm located directly above the array focuser 3, no focal point is found in the xy plane (as shown in fig. 11), indicating that the reflected terahertz wave is not focused. When a right circularly polarized terahertz wave having a frequency of 1THz is incident on the super surface polarizer 3, the reflected terahertz wave is output from the reflected terahertz wave output terminal 2, and at a position z =900 μm directly above the array focuser 3, there is no focus in the xy plane (as shown in fig. 12), which also indicates that the reflected terahertz wave is not focused. The implementation example shows that the device cannot realize focusing regulation and control on different polarization incident terahertz waves without structural arrangement designed according to the invention.
Claims (6)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111179781.1A CN113904120A (en) | 2021-10-11 | 2021-10-11 | Focused Terahertz Polarization Controller |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111179781.1A CN113904120A (en) | 2021-10-11 | 2021-10-11 | Focused Terahertz Polarization Controller |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113904120A true CN113904120A (en) | 2022-01-07 |
Family
ID=79190918
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111179781.1A Pending CN113904120A (en) | 2021-10-11 | 2021-10-11 | Focused Terahertz Polarization Controller |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113904120A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115167026A (en) * | 2022-08-04 | 2022-10-11 | 兰州大学 | A tunable multi-mode dual-frequency high-efficiency reflective polarization conversion device |
-
2021
- 2021-10-11 CN CN202111179781.1A patent/CN113904120A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115167026A (en) * | 2022-08-04 | 2022-10-11 | 兰州大学 | A tunable multi-mode dual-frequency high-efficiency reflective polarization conversion device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Fu et al. | Flexible terahertz beam manipulations based on liquid-crystal-integrated programmable metasurfaces | |
| CN107340559B (en) | High efficiency and broad band circular polarization switching device and method based on super clever surface | |
| US20180131100A1 (en) | Left-handed circular-polarization conversion metamaterial film | |
| US20180128953A1 (en) | Right-handed circular-polarization conversion metamaterial film | |
| Fang et al. | Asymmetric transmission of linearly polarized waves in terahertz chiral metamaterials | |
| Kou et al. | Terahertz switchable focusing planar lens with a nanoscale vanadium dioxide integrated metasurface | |
| CN111830620A (en) | Ultrathin transmission-type terahertz circularly-polarized asymmetric focusing lens | |
| CN112882259A (en) | Vanadium dioxide-based adjustable reflection-type terahertz polarization converter | |
| Jia et al. | Complementary chiral metasurface with strong broadband optical activity and enhanced transmission | |
| CN106707559B (en) | Function element based on graphene two dimension Meta Materials | |
| Shen et al. | A review on metasurface beam splitters | |
| KR20160010413A (en) | Optical Diode Comprising Components Made from Metamaterials | |
| Tan et al. | Free‐standing single‐layer metasurface for efficient and broadband tailoring of terahertz wavefront | |
| Wang et al. | Programmable manipulation of terahertz beams by hybrid graphene-metal coding metasurfaces | |
| CN109870824A (en) | An Efficient Terahertz Metamaterial Linear Polarization Converter | |
| CN111239882A (en) | Terahertz Bessel beam generator, preparation method and generation system | |
| CN110927993A (en) | Depolarizer based on all-dielectric metasurface structure | |
| CN113378372A (en) | Design method of terahertz vortex processor, product obtained by design method and application of product | |
| CN113904120A (en) | Focused Terahertz Polarization Controller | |
| CN117311054A (en) | Dynamic terahertz wave beam deflector with metal super-surface-liquid crystal-metal grating structure | |
| Liu et al. | Terahertz cascaded metasurfaces for both spin-symmetric and asymmetric beam diffractions with active power distribution | |
| Ma et al. | A dynamically switchable multifunctional meta-device in terahertz based on vanadium dioxide and photosensitive silicon | |
| WO2022088203A1 (en) | Tunable terahertz signal deflector and preparation method therefor | |
| Huang et al. | Graphene-enabled active terahertz focusing with wide tuning range | |
| Li et al. | Deep neural network-enabled multifunctional switchable terahertz metamaterial devices |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |