Broadband decoupling of intensity and polarization with vectorial Fourier metasurfaces

AbstractIntensity and polarization are two fundamental components of light. Independent control of them is of tremendous interest in many applications. In this paper, we propose a general vectorial encryption method, which enables arbitrary far-field light distribution with the local polarization, including orientations and ellipticities, decoupling intensity from polarization across a broad bandwidth using geometric phase metasurfaces. By revamping the well-known iterative Fourier transform algorithm, we propose “à la carte” design of far-field intensity and polarization distribution with vectorial Fourier metasurfaces. A series of non-conventional vectorial field distribution, mimicking cylindrical vector beams in the sense that they share the same intensity profile but with different polarization distribution and a speckled phase distribution, is demonstrated. Vectorial Fourier optical metasurfaces may enable important applications in the area of complex light beam generation, secure optical data storage, steganography and optical communications.

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Broadband Decoupling of Intensity and Polarization with Vectorial Fourier Metasurfaces

10.21203/rs.3.rs-140769/v1 ◽

2021 ◽

Author(s):

Qinghua Song ◽

Arthur Baroni ◽

Pin Chieh Wu ◽

Sébastien Chenot ◽

Virginie Brandli ◽

...

Keyword(s):

Data Storage ◽

Optical Communications ◽

Phase Distribution ◽

Optical Data Storage ◽

Optical Data ◽

Far Field ◽

Polarization Distribution ◽

Broad Bandwidth ◽

Local Polarization ◽

Encryption Method

Abstract Intensity and polarization are two fundamental components of light. Independently control of them is of tremendous interest in many applications. In this paper, we propose a general vectorial encryption method, which enables arbitrary far-field light distribution with the local polarization, including orientations and ellipticities, decoupling intensity from polarization across a broad bandwidth using geometric phase metasurfaces. By revamping the well-known iterative Fourier transform algorithm, we propose “à la carte” design of far-field intensity and polarization distribution with vectorial Fourier metasurfaces. A series of non-conventional vectorial field distribution, mimicking cylindrical vector beams in the sense that they share the same intensity profile but with different polarization distribution and a speckled phase distribution, is demonstrated. Vectorial Fourier optical metasurfaces may enable important applications in the area of complex light beam generation, secure optical data storage, steganography and optical communications.

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Far-field Diffraction Properties of Annular Walsh Filters

Advances in Optical Technologies ◽

10.1155/2013/360450 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 10

Author(s):

Pubali Mukherjee ◽

Lakshminarayan Hazra

Keyword(s):

Data Storage ◽

Walsh Function ◽

Optical Data Storage ◽

Optical Data ◽

Far Field ◽

Circular Aperture ◽

Orthogonal Functions ◽

Additional Degree ◽

Inner Radius ◽

Effective Use

Annular Walsh filters are derived from the rotationally symmetric annular Walsh functions which form a complete set of orthogonal functions that take on values either +1 or −1 over the domain specified by the inner and outer radii of the annulus. The value of any annular Walsh function is taken as zero from the centre of the circular aperture to the inner radius of the annulus. The three values 0, +1, and −1 in an annular Walsh function can be realized in a corresponding annular Walsh filter by using transmission values of zero amplitude (i.e., an obscuration), unity amplitude and zero phase, and unity amplitude and phase, respectively. Not only the order of the Walsh filter but also the size of the inner radius of the annulus provides an additional degree of freedom in tailoring of point spread function by using these filters for pupil plane filtering in imaging systems. In this report, we present the far-field amplitude characteristics of some of these filters to underscore their potential for effective use in several demanding applications like high-resolution microscopy, optical data storage, microlithography, optical encryption, and optical micromanipulation.

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High density optical data storage and fabrication of photonic crystals in photorefractive polymers for optical communications and networks

Optical Communications and Networks ◽

10.1142/9789812776280_0080 ◽

2002 ◽

Author(s):

Min Gu

Keyword(s):

Photonic Crystals ◽

Data Storage ◽

Optical Communications ◽

Optical Data Storage ◽

High Density ◽

Optical Data ◽

Photorefractive Polymers

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Structural and optical properties of amorphous Si–Ge–Te thin films prepared by combinatorial sputtering

Scientific Reports ◽

10.1038/s41598-021-91138-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

C. Mihai ◽

F. Sava ◽

I. D. Simandan ◽

A. C. Galca ◽

I. Burducea ◽

...

Keyword(s):

Optical Properties ◽

Data Storage ◽

Optical Sensors ◽

Material Selection ◽

Functional Materials ◽

Stability Study ◽

Optical Data Storage ◽

Optical Data ◽

Structural And Optical Properties ◽

Topological Constraint

AbstractThe lack of order in amorphous chalcogenides offers them novel properties but also adds increased challenges in the discovery and design of advanced functional materials. The amorphous compositions in the Si–Ge–Te system are of interest for many applications such as optical data storage, optical sensors and Ovonic threshold switches. But an extended exploration of this system is still missing. In this study, magnetron co-sputtering is used for the combinatorial synthesis of thin film libraries, outside the glass formation domain. Compositional, structural and optical properties are investigated and discussed in the framework of topological constraint theory. The materials in the library are classified as stressed-rigid amorphous networks. The bandgap is heavily influenced by the Te content while the near-IR refractive index dependence on Ge concentration shows a minimum, which could be exploited in applications. A transition from a disordered to a more ordered amorphous network at 60 at% Te, is observed. The thermal stability study shows that the formed crystalline phases are dictated by the concentration of Ge and Te. New amorphous compositions in the Si–Ge–Te system were found and their properties explored, thus enabling an informed and rapid material selection and design for applications.

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Optical Isomerization and Photo-Patternable Properties of GeO2/Ormosils Organic-Inorganic Composite Films Doped with Azobenzene

Coatings ◽

10.3390/coatings11070818 ◽

2021 ◽

Vol 11 (7) ◽

pp. 818

Author(s):

Xuehua Zhang ◽

Qian Wang ◽

Shun Liu ◽

Wei Zhang ◽

Fangren Hu ◽

...

Keyword(s):

Optical Waveguide ◽

Data Storage ◽

Optical Switching ◽

Sol Gel ◽

Composite Films ◽

Optical Data Storage ◽

Optical Data ◽

Single Chip ◽

Coating Method ◽

Inorganic Composite

GeO2/organically modified silane (ormosils) organic-inorganic composite films containing azobenzene were prepared by combining sol-gel technology and spin coating method. Optical waveguide properties including the refractive index and thickness of the composite films were characterized by using a prism coupling instrument. Surface morphology and photochemical properties of the composite films were investigated by atomic force microscope and Fourier transform infrared spectrometer. Results indicate that the composite films have smooth and neat surface, and excellent optical waveguide performance. Photo-isomerization properties of the composite films were studied by using a UV–Vis spectrophotometer. Optical switching performance of the composite films was also studied under the alternating exposure of 365 nm ultraviolet light and 410 nm visible light. Finally, strip waveguides and microlens arrays were built in the composite films through a UV soft imprint technique. Based on the above results, we believe that the prepared composite films are promising candidates for micro-nano optics and photonic applications, which would allow directly integrating the optical data storage and optical switching devices onto a single chip.

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