CN111208594B - Super-grating element structure insensitive to broadband visible light polarization and application thereof - Google Patents

Super-grating element structure insensitive to broadband visible light polarization and application thereof Download PDF

Info

Publication number
CN111208594B
CN111208594B CN202010180206.2A CN202010180206A CN111208594B CN 111208594 B CN111208594 B CN 111208594B CN 202010180206 A CN202010180206 A CN 202010180206A CN 111208594 B CN111208594 B CN 111208594B
Authority
CN
China
Prior art keywords
silver
visible light
broadband
dispersion
insensitive
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.)
Expired - Fee Related
Application number
CN202010180206.2A
Other languages
Chinese (zh)
Other versions
CN111208594A (en
Inventor
万成伟
李仲阳
郑国兴
李子乐
代尘杰
邓联贵
杨睿
时阳阳
万帅
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.)
Wuhan University WHU
Original Assignee
Wuhan University WHU
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 Wuhan University WHU filed Critical Wuhan University WHU
Priority to CN202010180206.2A priority Critical patent/CN111208594B/en
Publication of CN111208594A publication Critical patent/CN111208594A/en
Application granted granted Critical
Publication of CN111208594B publication Critical patent/CN111208594B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/18—Diffraction gratings
    • G02B5/1809—Diffraction gratings with pitch less than or comparable to the wavelength
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/18—Diffraction gratings
    • G02B5/1814—Diffraction gratings structurally combined with one or more further optical elements, e.g. lenses, mirrors, prisms or other diffraction gratings

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Polarising Elements (AREA)

Abstract

The invention discloses a broadband visible light polarization insensitive ultra-grating element structure and application thereof. The element structure is an array composed of unit structures, and each silver geometric body, a silicon dioxide layer and a silver reflecting layer corresponding to the silver geometric body form the unit structures; the unit structure has broadband response to visible light; the unit structure is insensitive to polarization; the unit structures are periodically arranged to form an array, so that broadband dispersion can be realized. The invention has small structure scale, easy integration, strong capability of dispersing visible light wave band and large coverage range of dispersion angle, and can be used for optical wave frequency analysis in spectrometers, spectrometers and the like.

Description

Super-grating element structure insensitive to broadband visible light polarization and application thereof
Technical Field
The invention relates to the field of micro-nano optics and optical dispersion, in particular to a broadband visible light polarization insensitive ultra-grating element structure and application thereof.
Background
The conventional optical dispersion phenomenon is caused by the propagation speed (refractive index) of light along with the frequency (wavelength) of the light wave when the light propagates in a medium. The traditional dispersion element comprises a prism and a grating, and the dispersion of the prism depends on accumulated optical path difference, so that the element size is larger; the grating uses diffraction phenomena, and the resulting dispersion will exist in order ± 1 and other orders. For common super-surfaces, such planar structures are typically very sensitive to light polarization, i.e. exhibit different optical responses for different polarizations, due to the properties of the materials and the specific geometry. Second, conventional gratings, which operate on the basis of conventional geometric and diffractive optics, operate on the principle of passing light through a periodically arranged array to cause rapid changes in phase and/or polarization. However, both critical optical fields, plasma and diffractive optics, have been independently studied and developed. Therefore, the research and investigation of the architectural hybridization between the plasma super surface and the general diffraction grating is insufficient. Also, it is unclear in the field of nanophotonics how the interaction between the plasmon effect and the grating effect affects the performance of emerging nanoscale optical devices.
In recent years, elements having a dispersion function based on a metamaterial have been proposed, and the adjustment of the phase of an optical wave is changed from an accumulation process of an optical path difference to a phase gradient change of a two-dimensional surface based on a generalized catadioptric law. The phase change of the two-dimensional surface can be used for realizing the regulation and control of the refraction or reflection angle, so that the dispersion element is reduced to an ultramicro size. There are some problems to be solved. For example, "Li Z, Palacios E, Butun S, et al, visual-frequency measurements for broadband and polarization recovery and high-efficiency polarization [ J ]. Nano drivers, 2015,15(3): 1615-.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a broadband visible light polarization insensitive ultra-grating element structure and application thereof.
In order to achieve the purpose, the scheme provided by the invention is as follows:
in a first aspect, the present invention provides a broadband visible light polarization insensitive supergrating device structure, characterized in that: comprises a dielectric substrate layer; the dielectric substrate layer is composed of a lower silver reflecting layer and an upper silicon dioxide layer;
a plurality of silver geometric bodies with the same size are arranged on the silicon dioxide layer; the silver geometric bodies are arranged on the medium substrate layer in a cycle of 800nm in the X direction and 200nm in the Y direction; the structural sizes of the silver geometric bodies are all sub-wavelength sizes;
each silver geometry and the 800 x 200nm underneath it2The silicon dioxide layer and the silver reflecting layer form a unit structure; the unit structure is insensitive to polarization and responds to broadband visible light wave band(ii) a The unit structures are periodically arranged in the X direction with 800nm and the Y direction with 200nm as a period to form an array, so that broadband dispersion can be realized.
Preferably, the silver geometric body is of a frustum pyramid structure.
Further, an optimally designed unit structure is obtained by taking the dispersion effect of the broadband as an optimization object; the width of the wide side of the silver geometry is W1The height of the wide side is H1The width of the narrow side is W2And the height of the narrow side is H2(ii) a The thickness of the silicon dioxide layer is d;
the optimization parameters are as follows: w1＝100nm、H1＝30nm、W2＝30nm、H2＝100nm，d＝30nm；
The size of the unit structure is 800nm at the long side and 200nm at the short side.
In a second aspect, the present invention provides an application of the above-mentioned ultra-grating device structure insensitive to broadband visible light polarization in realizing high-performance dispersion in the visible light band.
Compared with the traditional element, the invention has the following advantages and beneficial effects:
(1) the dispersion element of the invention has strong dispersion capability and large dispersion angle range, and only has + 1-level dispersion.
(2) The unit structure of the element has ultramicro size, so the element also has the important advantages of small volume, light weight, easy integration and the like, and can be widely applied to the field of spectrometer integration and other photon integration.
Drawings
FIG. 1 is a schematic diagram of the structure of a unit according to the present invention;
FIG. 2 is a schematic diagram of the arrangement of the unit structure array according to the present invention;
FIG. 3 is a simulation graph of the variation of the dispersion angle with the wavelength after the element is vertically irradiated by the linearly polarized light in the x direction in the embodiment of the present invention;
FIG. 4 is a simulation graph showing the variation of the dispersion angle with the wavelength after the element is vertically irradiated by the linearly polarized light in the y direction in the embodiment of the present invention;
FIG. 5 is a simulated plot of dispersion angle as a function of wavelength after orthogonally polarized light perpendicularly illuminates an element in an embodiment of the present invention;
in the figure: w1Is the width H of the wide side of the silver geometric body1Is the height, W, of the silver geometric body broadside2Is the width H of the narrow side of the silver geometric body2Is the height of the narrow side of the silver geometry.
Detailed Description
In order to more clearly explain the structure of the present invention and the functions realized by the same, the present invention is further described in detail by referring to the specific embodiments in the attached drawings.
Example 1
The embodiment is a specific design process of a broadband visible light polarization insensitive ultra-grating element structure.
Optimizing and designing the unit structure by using electromagnetic simulation software FDTD Solutions, taking the dispersion effect of a broadband as an optimization object, and scanning the width W of the wide side of the silver geometric body1Height H of the broadside1Width W of narrow side2And the height H of the narrow side2The thickness d of the silicon dioxide layer, to obtain the optimum parameters for the desired function. Through optimization calculation, the finally obtained optimization parameter is W1＝100nm、H1＝30nm、W2＝30nm、H2The unit structure has the size of a long side of 800nm and a short side of 200nm, wherein d is 100nm and 30 nm. Fig. 1 is a schematic diagram of a cell structure. The unit structures are periodically arranged in the x-direction and the y-direction, as shown in fig. 2, to constitute a silver geometrical array. When a beam of white light is vertically incident on the array surface from right above the array, an abnormal reflection phenomenon occurs, and meanwhile, light with different wavelengths is reflected to different angles, namely, the dispersion of light waves. FIG. 3 simulates the dispersion effect of linearly polarized white light vibrating in the x-direction incident on the array surface using software; similarly, fig. 4 shows the dispersion effect of linearly polarized white light vibrating in the y-direction incident on the surface of the silver geometric array. When white light having an arbitrary polarization state is incident, light corresponding to light having an orthogonal polarization state is incident on the surface of the silver geometry, and the dispersion effect thereof is shown in fig. 5.
In order to facilitate understanding of the technical solution of the present invention, the technical principle that the structure of the present invention can realize the structure of the polarization insensitive ultra-thin visible light broadband dispersion element will be described in detail below:
according to the generalized law of reflection:
Figure GDA0002787907000000041
in the formula [ theta ]iAnd thetarRespectively angle of incidence and angle of reflection, lambda0For the wavelength of the light wave, phi (x) is the phase gradient of the surface along the x-direction, niIs the refractive index of the incident medium. According to the formula, when
Figure GDA0002787907000000051
Is a constant, then the reflection angle thetarThe dispersion phenomenon is caused by the wavelength of the incident light wave, i.e. light waves of different wavelengths have different reflection angles. The design of such a phase gradient is usually in a single direction, i.e. a phase gradient
Figure GDA0002787907000000052
Or
Figure GDA0002787907000000053
The invention designs the constant type phase gradient in the x direction as a constant, and the phase gradient in the x direction can cause the linear polarized light vibrating in the y direction to generate an abnormal reflection phenomenon, namely a dispersion effect.
Since linearly polarized light oscillating in the x direction is insensitive to this phase gradient, the idea of blazed grating is used in the present invention. The blazed grating utilizes the non-parallel of the groove surface and the grating surface to separate the central maximum of single groove surface diffraction from the interference zero-order principal maximum among the groove surfaces, and transfers and concentrates the light energy to a certain level of spectrum from the interference zero-order principal maximum to realize the blazed of the level of spectrum. By utilizing the principle and the idea of blaze, according to the illustration in fig. 1, the silver geometric body has a certain gradient in the z direction, and the dispersion effect same as that of polarized light vibrating in the y direction can be realized for linearly polarized light vibrating in the x direction by optimizing the height and the size of the gradient. And the problem that the original blazed grating is only used for one specific wavelength is solved, so that the working wavelength of the blazed grating is changed into a broadband wavelength.
Example 2
The embodiment is a specific design process of a broadband visible light super-grating with adjustable light splitting and absorption functions.
And optimally designing a unit structure by using electromagnetic simulation software FDTD Solutions, taking the abnormal deflection effect of the light beam as an optimization object, and scanning the width of the wide side, the height of the wide side, the width of the narrow side, the height of the narrow side and the thickness of the silicon dioxide layer of the silver geometric body to obtain the optimal parameters under the expected function. The unit structures are periodically arranged along the x direction and the y direction to form a silver geometrical body array. When a beam of white light vertically enters the array surface from right above the array, the phenomenon that different polarized lights go to different directions occurs, and meanwhile, the lights with different wavelengths are reflected to different angles, so that the light splitting function is realized. When the angle of the incident light is changed, the reflection efficiency is different for the incident light with different angles, and the absorption adjustable function is realized.
The embodiment designs the change of a constant phase gradient in the x direction, and the phase gradient can enable linearly polarized light vibrating along the y direction to generate an abnormal reflection phenomenon; since linearly polarized light vibrating in the x direction is insensitive to this phase gradient, the principle of blazed grating is employed in this example such that linearly polarized light vibrating in the x direction produces a reflection phenomenon opposite to the y direction polarization. The groove surface of the blazed grating is not parallel to the grating surface, so that light energy is gathered to a certain level of spectrum from the interference zero order main maximum, and the blazed spectrum is realized. By utilizing the principle and thought, the silver geometric body of the embodiment has a certain gradient in the z direction, and the dispersion effect same as that of polarized light vibrating in the y direction on linearly polarized light vibrating in the x direction can be realized by optimizing the gradient.
In summary, the invention combines two different principles and methods to design an ultrathin visible light broadband dispersion element structure insensitive to polarization, which has the same dispersion effect on linearly polarized light in the x direction and the y direction. Therefore, the device can be used as a dispersion device for light waves in any polarization state.

Claims (3)

1. A broadband visible light polarization insensitive supergrating element structure, comprising: comprises a dielectric substrate layer; the medium substrate layer is composed of a lower silver reflecting layer (3) and an upper silicon dioxide layer (2);
a plurality of silver geometric bodies (1) with the same size are arranged on the silicon dioxide layer; the silver geometric bodies (1) are arranged on the medium substrate layer in a cycle of 800nm in the X direction and 200nm in the Y direction; the structural sizes of the silver geometric bodies (1) are all sub-wavelength sizes;
each silver geometry (1) and the 800 x 200nm underneath it2The silicon dioxide layer (2) and the silver reflecting layer (3) form a unit structure; the unit structure responds to a broadband visible light wave band and is insensitive to polarization; the unit structures are periodically arranged in the X direction with 800nm and the Y direction with 200nm as a period to form an array, so that broadband dispersion can be realized;
the silver geometric body (1) is of a frustum structure with a slope in the Z direction and wide at the top and narrow at the bottom.
2. A broadband visible light polarization insensitive supergrating element structure according to claim 1, wherein: obtaining an optimally designed unit structure by taking the dispersion effect of the broadband as an optimization object; the width of the wide side of the silver geometric body (1) is W1The height of the wide side is H1The width of the narrow side is W2And the height of the narrow side is H2(ii) a The thickness of the silicon dioxide layer (2) is d;
the optimization parameters are as follows: w1＝100nm、H1＝30nm、W2＝30nm、H2＝100nm，d＝30nm；
The size of the unit structure is 800nm at the long side and 200nm at the short side.
3. Use of a broadband visible light polarization insensitive supergrating element structure as claimed in claim 1 or 2 for achieving high performance dispersion in the visible wavelength band.
CN202010180206.2A 2020-03-16 2020-03-16 Super-grating element structure insensitive to broadband visible light polarization and application thereof Expired - Fee Related CN111208594B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010180206.2A CN111208594B (en) 2020-03-16 2020-03-16 Super-grating element structure insensitive to broadband visible light polarization and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010180206.2A CN111208594B (en) 2020-03-16 2020-03-16 Super-grating element structure insensitive to broadband visible light polarization and application thereof

Publications (2)

Publication Number Publication Date
CN111208594A CN111208594A (en) 2020-05-29
CN111208594B true CN111208594B (en) 2021-07-06

Family

ID=70784608

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010180206.2A Expired - Fee Related CN111208594B (en) 2020-03-16 2020-03-16 Super-grating element structure insensitive to broadband visible light polarization and application thereof

Country Status (1)

Country Link
CN (1) CN111208594B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113325490B (en) * 2021-05-27 2022-04-12 武汉大学 Light-deflection super surface based on hydrophilic-hydrophobic selective infiltration regulation

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011509418A (en) * 2007-12-10 2011-03-24 リサーチ・ファウンデーション・オブ・ザ・シティー・ユニヴァーシティー・オブ・ニュー・ヨーク Subwavelength structure, apparatus and method for light control in material composites
EP2596400A4 (en) * 2010-07-22 2017-08-30 University of Pittsburgh - Of the Commonwealth System of Higher Education Nano-optic refractive optics
CN102520471A (en) * 2011-12-30 2012-06-27 中国科学院上海光学精密机械研究所 Polarization-independent wide band reflection grating
CN105891925B (en) * 2016-04-18 2019-04-19 中国科学院上海光学精密机械研究所 1064 nanometers of polarization independent wideband high-diffraction efficiency bilayer reflection-type all dielectric gratings
CN108121022A (en) * 2016-11-30 2018-06-05 上海矽越光电科技有限公司 A kind of polarization-independent wide band reflection grating
CN108761610A (en) * 2018-06-13 2018-11-06 成都精密光学工程研究中心 Regulate and control the unrelated reflective dielectric grating of polarization of film based on refractive index
CN109491001B (en) * 2018-12-12 2021-06-04 成都精密光学工程研究中心 Polarization-independent grating based on covering refractive index matching layer and preparation method thereof
CN109799556A (en) * 2019-03-11 2019-05-24 浙江科技学院 Polarization independent wideband absorber based on doped silicon grating array
CN110196464B (en) * 2019-07-01 2022-07-29 江南大学 Method for realizing ultra-wideband light absorption and composite microstructure
CN110346854B (en) * 2019-07-18 2022-05-20 江西师范大学 Ultra-narrow multi-band tunable perfect absorber irrelevant to polarization

Also Published As

Publication number Publication date
CN111208594A (en) 2020-05-29

Similar Documents

Publication Publication Date Title
US9507064B2 (en) Dielectric metasurface optical elements
US11543653B2 (en) Device components formed of geometric structures
CN110333560B (en) Broadband achromatic device based on medium super surface
AU2011281097B2 (en) Nano-optic refractive optics
CN112748484B (en) Dual-functional super surface
CN112630869B (en) Polarization device based on diffraction chiral metamaterial, preparation method and photoelectronic device
CN110441843B (en) Optical device based on surface plasmon lattice point resonance
CN111045121B (en) Polarization-controlled surface plasmon dual-function super surface and design and preparation method thereof
KR20200141443A (en) Diffraction grating containing a dual material structure
CN102792456A (en) Solar cell, solar cell panel, and device comprising solar cell
CN106949971A (en) A kind of compact polarization state measuring instrument based on the super surface of medium
CN104777532A (en) Ultra-narrow-band TE (transverse electric) polarizing spectrum selective absorber based on cascaded fiber grating structure
CN112558218A (en) All-dielectric transmission type efficient ultrathin beam splitter and preparation method and application thereof
CN110568540B (en) Micro-nano wave plate array with double-image display function and construction method thereof
CN111766651B (en) Linearly polarized light one-way SP exciter, circularly polarized light directional SP exciter, multidirectional beam splitter and polarization detection method thereof
CN107976733A (en) A kind of all dielectric polarizes unrelated angular filter
CN111208594B (en) Super-grating element structure insensitive to broadband visible light polarization and application thereof
CN112909565A (en) Multi-waveband absorber with mixed patterned metal-graphene super-surface
CN114488366A (en) Reflective polarization double-focusing plasma super lens and preparation method thereof
CN111694078B (en) MIM grid lattice plasmon absorber
CN111580197B (en) Transverse MIMI lattice plasmon resonance absorber
Gao et al. Ultra-dispersive anomalous diffraction from Pancharatnam-Berry metasurfaces
CN112484667B (en) Photoelectric angle sensor based on two-dimensional material light absorption structure array
Sadeghi et al. Chiral In-Plane Light Scattering in Arrays of L-Shaped Au Nanoantennas via Photon-Spin-Dependent Lattice Modes
Fu et al. Using periodic trapezoidal Ag strips and silicon dioxide slab for polarization-independent narrowband absorber

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
GR01 Patent grant
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20210706

CF01 Termination of patent right due to non-payment of annual fee