Showing papers on "Birefringence published in 2020"

First-principles experimental demonstration of ferroelectricity in a thermotropic nematic liquid crystal: Polar domains and striking electro-optics.

Abstract: We report the experimental determination of the structure and response to applied electric field of the lower-temperature nematic phase of the previously reported calamitic compound 4-[(4-nitrophenoxy)carbonyl]phenyl2,4-dimethoxybenzoate (RM734). We exploit its electro-optics to visualize the appearance, in the absence of applied field, of a permanent electric polarization density, manifested as a spontaneously broken symmetry in distinct domains of opposite polar orientation. Polarization reversal is mediated by field-induced domain wall movement, making this phase ferroelectric, a 3D uniaxial nematic having a spontaneous, reorientable polarization locally parallel to the director. This polarization density saturates at a low temperature value of ∼6 µC/cm2, the largest ever measured for a fluid or glassy material. This polarization is comparable to that of solid state ferroelectrics and is close to the average value obtained by assuming perfect, polar alignment of molecular dipoles in the nematic. We find a host of spectacular optical and hydrodynamic effects driven by ultralow applied field (E ∼ 1 V/cm), produced by the coupling of the large polarization to nematic birefringence and flow. Electrostatic self-interaction of the polarization charge renders the transition from the nematic phase mean field-like and weakly first order and controls the director field structure of the ferroelectric phase. Atomistic molecular dynamics simulation reveals short-range polar molecular interactions that favor ferroelectric ordering, including a tendency for head-to-tail association into polar, chain-like assemblies having polar lateral correlations. These results indicate a significant potential for transformative, new nematic physics, chemistry, and applications based on the enhanced understanding, development, and exploitation of molecular electrostatic interaction.

Continuous angle-tunable birefringence with freeform metasurfaces for arbitrary polarization conversion

Abstract: Birefringence occurs when light with different polarizations sees different refractive indices during propagation. It plays an important role in optics and has enabled essential polarization elements such as wave plates. In bulk crystals, it is typically constrained to linear birefringence. In metamaterials with freeform meta-atoms, however, one can engineer the optical anisotropy such that light sees different indices for arbitrary-linear, circular, or elliptical-orthogonal eigen-polarization states. Using topology-optimized metasurfaces, we demonstrate this arbitrary birefringence. It has the unique feature that it can be continuously tuned from linear to elliptical birefringence, by changing the angle of incidence. In this way, a single metasurface can operate as many wave plates in parallel, implementing different polarization transformations. Angle-tunable arbitrary birefringence expands the scope of polarization optics, enables compact and versatile polarization operations that would otherwise require cascading multiple elements, and may find applications in polarization imaging, quantum optics, and other areas.

Ultralow-loss geometric phase and polarization shaping by ultrafast laser writing in silica glass

Abstract: Polarization and geometric phase shaping via a space-variant anisotropy has attracted considerable interest for fabrication of flat optical elements and generation of vector beams with applications in various areas of science and technology. Among the methods for anisotropy patterning, imprinting of self-assembled nanograting structures in silica glass by femtosecond laser writing is promising for the fabrication of space-variant birefringent optics with high thermal and chemical durability and high optical damage threshold. However, a drawback is the optical loss due to the light scattering by nanograting structures, which has limited the application. Here, we report a new type of ultrafast laser-induced modification in silica glass, which consists of randomly distributed nanopores elongated in the direction perpendicular to the polarization, providing controllable birefringent structures with transmittance as high as 99% in the visible and near-infrared ranges and >90% in the UV range down to 330 nm. The observed anisotropic nanoporous silica structures are fundamentally different from the femtosecond laser-induced nanogratings and conventional nanoporous silica. A mechanism of nanocavitation via interstitial oxygen generation mediated by multiphoton and avanlanche defect ionization is proposed. We demonstrate ultralow-loss geometrical phase optical elements, including geometrical phase prism and lens, and a vector beam convertor in silica glass.

Cubic-quartic optical solitons in birefringent fibers with four forms of nonlinear refractive index by exp-function expansion

Abstract: This paper applies exp-function expansion algorithm to secure to cubic-quartic dark and singular optical solitons in birefringent fibers that are studied with four forms of nonlinear refractive index. These solitons are listed along with their existence criteria and are also classified.

CsAlB3O6F: a beryllium-free deep-ultraviolet nonlinear optical material with enhanced thermal stability

Abstract: The design of new beryllium-free deep-ultraviolet nonlinear optical materials is important but challenging. Here, we describe a new strategy to search for such materials based on rational selection of fundamental structural units. By combining asymmetric AlO3F tetrahedra and π-conjugated B3O6 rings, a new aluminum borate fluoride, CsAlB3O6F was obtained. It exhibits excellent linear and nonlinear optical properties including a high optical transmittance with a cut-off edge shorter than 190 nm, large second harmonic generation intensities (2.0× KH2PO4, KDP), and suitable birefringence for phase-matching under 200 nm. It also has good thermal stability and can be synthesized easily in an open system.

BaF2TeF2(OH)2: A UV Nonlinear Optical Fluorotellurite Material Designed by Band-Gap Engineering.

Abstract: Balancing the wide band gap, large second harmonic generation (SHG) response, and moderate birefringence are significant but addressable challenges for designing nonlinear optical (NLO) materials. ...

A Refractive Index Sensor Based on H-Shaped Photonic Crystal Fibers Coated with Ag-Graphene Layers.

Abstract: An Ag-graphene layers-coated H-shaped photonic crystal fiber (PCF) surface plasmon resonance (SPR) sensor with a U-shaped grooves open structure for refractive index (RI) sensing is proposed and numerically simulated by the finite element method (FEM). The designed sensor could solve the problems of air-holes material coating and analyte filling in PCF. Two big air-holes in the x-axis produce a birefringence phenomenon leading to the confinement loss and sensitivity of x-polarized light being much stronger than y-polarized. Graphene is deposited on the layer of silver in the grooves; its high surface to volume ratio and rich π conjugation make it a suitable dielectric layer for sensing. The effect of structure parameters such as air-holes size, U-shaped grooves depth, thickness of the silver layer and number of graphene layers on the sensing performance of the proposed sensor are numerical simulated. A large analyte RI range from 1.33 to 1.41 is calculated and the highest wavelength sensitivity is 12,600 nm/RIU. In the linear RI sensing region of 1.33 to 1.36; the average wavelength sensitivity we obtained can reach 2770 nm/RIU with a resolution of 3.61 × 10-5 RIU. This work provides a reference for developing a high-sensitivity; multi-parameter measurement sensor potentially useful for water pollution monitoring and biosensing in the future.

Two Pyrophosphates with Large Birefringences and Second-Harmonic Responses as Ultraviolet Nonlinear Optical Materials

Abstract: Two new pyrophosphates nonlinear optical (NLO) materials, Rb3 PbBi(P2 O7 )2 (I) and Cs3 PbBi(P2 O7 )2 (II), were successfully designed and synthesized. Both compounds exhibit large NLO effects and birefringences. Material I presents the scarce case of possessing the coexistence of large birefringence (0.031 at 1064 nm and 0.037 at 532 nm) and second harmonic generation (SHG) response (2.8× potassium dihydrogen phosphate (KDP)) in ultraviolet NLO phosphates and its SHG is the largest in the phase-matching (PM) pyrophosphates. Both I and II have three-dimensional (3D) crystal structures composed of corner-shared RbO12 (CsO11 ), RbO10 (CsO10 ), BiO6 , PbO7 (PbO6 ) and P2 O7 groups, in which P2 O7 and PbO7 (PbO6 ) units form an alveolate [PbPO]∞ skeleton frame. Theoretical calculations reveal that the P-O, Bi-O and Pb-O units are mainly responsible for the moderate birefringence and large SHG efficiency of I.

Enhanced nonlinear optical functionality in birefringence and refractive index dispersion of the deep-ultraviolet fluorooxoborates

Abstract: As a promising candidate, the fluorooxoborate has enkindled new explorations of nonlinear optical materials to meet the deep-ultraviolet criteria. However, big challenges and open questions still remain facing this exciting new field, especially the birefringence and dispersion of refractive index which are fundamental parameters for determining the phase-matching second harmonic generation wavelength. Here we designed possible anionic groups in fluorooxoborates, and analyzed the optical anisotropy to check its influence on birefringence, which was proved further by the response electronic distribution anisotropy approximation. The functional modules modulating birefringence in fluorooxoborates were explored systematically. We developed an approach for evaluating the behavior of the refractive index dispersions and found that the fluorooxoborates had small refractive index dispersions owing to the introduction of fluorooxoborate modules. Our results demonstrate that fluorooxoborates can be utilized to realize short phase-matching wavelength markedly and offer a path toward novel performance-driven materials design.

Atacama Cosmology Telescope: Constraints on cosmic birefringence

Abstract: We present new constraints on anisotropic birefringence of the cosmic microwave background polarization using two seasons of data from the Atacama Cosmology Telescope covering 456 square degrees of sky. The birefringence power spectrum, measured using a curved-sky quadratic estimator, is consistent with zero. Our results provide the tightest current constraint on birefringence over a range of angular scales between 5 arc minutes and 9°. We improve previous upper limits on the amplitude of a scale-invariant birefringence power spectrum by a factor of between 2 and 3. Assuming a nearly massless axion field during inflation, our result is equivalent to a 2σ upper limit on the Chern-Simons coupling constant between axions and photons of gαγ<4.0×10−2/HI, where HI is the inflationary Hubble scale.

Optical properties of metasurfaces infiltrated with liquid crystals

Abstract: Optical metasurfaces allow the ability to precisely manipulate the wavefront of light, creating many interesting and exotic optical phenomena. However, they generally lack dynamic control over their optical properties and are limited to passive optical elements. In this work, we report the nontrivial infiltration of nanostructured metalenses with three respective nematic liquid crystals of different refractive index and birefringence. The optical properties of the metalens are evaluated after liquid-crystal infiltration to quantify its effect on the intended optical design. We observe a significant modification of the metalens focus after infiltration for each liquid crystal. These optical changes result from modification of local refractive index surrounding the metalens structure after infiltration. We report qualitative agreement of the optical experiments with finite-difference time-domain solver (FDTD) simulation results. By harnessing the tunability inherent in the orientation dependent refractive index of the infiltrated liquid crystal, the metalens system considered here has the potential to enable dynamic reconfigurability in metasurfaces.

Femtosecond dual-comb Yb:CaF2 laser from a single free-running polarization-multiplexed cavity for optical sampling applications.

Abstract: Dual optical frequency combs are an appealing solution to many optical measurement techniques due to their high spectral and temporal resolution, high scanning speed, and lack of moving parts. However, industrial and field-deployable applications of such systems are limited due to a high-cost factor and intricacy in the experimental setups, which typically require a pair of locked femtosecond lasers. Here, we demonstrate a single oscillator which produces two mode-locked output beams with a stable repetition rate difference. We achieve this via inserting two 45°-cut birefringent crystals into the laser cavity, which introduces a repetition rate difference between the two polarization states of the cavity. To mode-lock both combs simultaneously, we use a semiconductor saturable absorber mirror (SESAM). We achieve two simultaneously operating combs at 1050 nm with 175-fs duration, 3.2-nJ pulses and an average power of 440 mW in each beam. The average repetition rate is 137 MHz, and we set the repetition rate difference to 1 kHz. This laser system, which is the first SESAM mode-locked femtosecond solid-state dual-comb source based on birefringent multiplexing, paves the way for portable and high-power femtosecond dual-combs with flexible repetition rate. To demonstrate the utility of the laser for applications, we perform asynchronous optical sampling (ASOPS) on semiconductor thin-film structures with the free-running laser system, revealing temporal dynamics from femtosecond to nanosecond time scales.

Direct Visualizing the Spin Hall Effect of Light via Ultrahigh-Order Modes.

Abstract: We report an experiment showing the submillimeter Imbert-Fedorov shift from the ultrastrong spin-orbital angular momentum coupling, which is a photonic version of the spin Hall effect, by measuring the reflection of light from the surface of a birefringent symmetrical metal cladding planar waveguide. The light incidents at a near-normal incident angle and excites resonant ultrahigh-order modes inside the waveguide. A 0.16-mm displacement of separated reflected light spots corresponding to two polarization states is distinguishable by human eyes. In our experiment, we demonstrate the control of polarizations of light and the direct observation of the spin Hall effect of light, which opens an important avenue towards potential applications for optical sensing and quantum information processing, where the spin nature of photons exhibits key features.

An Exceptional Peroxide Birefringent Material Resulting from d–π Interactions

Abstract: Birefringent materials, which can modulate the polarization of light, are almost exclusively limited to oxides. Peroxides have long been overlooked as birefringent materials, because they are usually not stable in air. Now, the first peroxide birefringent material Rb2 VO(O2 )2 F is reported, the single crystals of which keep transparency after being exposed in the air for two weeks. Interestingly, Rb2 VO(O2 )2 F does not feature an optimal anisotropic structure, but its birefringence (Δn=0.189 at 546 nm) exceeds those of the majority of oxides. According to the first-principles calculations, this exceptional birefringence should be attributed to the strong electronic interactions between localized π orbital of O22- anions and V5+ 3d orbitals, which may be also favorable to the stability in the air for Rb2 VO(O2 )2 F. These findings distinguish peroxides as a brand-new class of birefringent materials that may possess birefringence superior to the traditional oxides.

Surface Plasmon Resonance Induced High Sensitivity Temperature and Refractive Index Sensor Based on Evanescent Field Enhanced Photonic Crystal Fiber

Abstract: An ultra high-sensitivity temperature and refractive index (RI) sensor based on surface plasmon resonance (SPR) effect in D-shape high birefringence photonic crystal fiber (PCF) is presented and discussed by the finite element method (FEM). The designed PCF is polished to enhance the interaction of the evanescent field with the external medium, ultimately improving the sensing performance. The influence of three different plasma materials, gold, silver and aluminum, on the sensing performance was investigated. Finally, the chemically stable plasma material gold is selected to coat on flat surface of D-shape PCF for SPR sensing, realizing the sensitive real-time monitoring of RI and temperature. The sensing performance was greatly improved, with a wide RI (1.43 to 1.50) and temperature (36 $^{\circ }$ C to 86 $^{\circ }$ C) detection range, and the corresponding maximum sensitivity was 44850 nm/RIU and −16.875 nm/ $^{\circ }$ C, respectively. Furthermore, the sensitivity is not particularly sensitive to the sizes of the designed air holes, which leads to a sensor with high structure tolerance. Numerical results show that the coating thickness not only affects the sensitivity but also the detection range of the sensor, so we can tune the RI and temperature detection range by adjusting the gold film thickness to meet specific detection requirements. The sensor with enhanced sensitivity, tunable detection range, and high fabrication tolerance has a wide application prospect in the field of life science research, chemical production, and environmental monitoring.

Investigation of optical solitons in birefringent polarization preserving fibers with four-wave mixing effect

Abstract: The paper studies the optical solitons with coupled nonlinear Schrodinger system (CNLSS) that describes the propagation of waves in birefringence polarization-preserving fibers with four-wave mixin...

Pushing periodic-disorder-induced phase matching into the deep-ultraviolet spectral region: theory and demonstration.

Abstract: Nonlinear frequency conversion is a ubiquitous technique that is used to obtain broad-range lasers and supercontinuum coherent sources. The phase-matching condition (momentum conservation relation) is the key criterion but a challenging bottleneck in highly efficient conversion. Birefringent phase matching (BPM) and quasi-phase matching (QPM) are two feasible routes but are strongly limited in natural anisotropic crystals or ferroelectric crystals. Therefore, it is in urgent demand for a general technique that can compensate for the phase mismatching in universal nonlinear materials and in broad wavelength ranges. Here, an additional periodic phase (APP) from order/disorder alignment is proposed to meet the phase-matching condition in arbitrary nonlinear crystals and demonstrated from the visible region to the deep-ultraviolet region (e.g., LiNbO3 and quartz). Remarkably, pioneering 177.3-nm coherent output is first obtained in commercial quartz crystal with an unprecedented conversion efficiency above 1‰. This study not only opens a new roadmap to resuscitate those long-neglected nonlinear optical crystals for wavelength extension, but also may revolutionize next-generation nonlinear photonics and their further applications.

A microcrystal method for the measurement of birefringence

Abstract: Based on the interference principle, a special test process to measure polycrystalline birefringence was proposed and confirmed as an effective method for screening anisotropic micro-crystals. In this process, an innovative automatic mesh sieve was designed and applied to sieve the crystal particles of Al2O3, SiO2, KDP, LBO and BBO. Each crystal was accurately divided into four thickness ranges of 23–38 μm, 38–53 μm, 53–90 μm, and 90–150 μm experimentally, and the polarization interference method was employed to measure the birefringence of the samples. Results showed that, when the thickness of the crystal particle was taken as the intermediate value of the mesh width in the range of 38–53 μm, the experimental value of the birefringence of the crystal particles on a small scale was closest to that of the large crystals.

Hollow-core photonic quasicrystal fiber with high birefringence and ultra-low nonlinearity

Abstract: A hollow-core fiber based on photonic quasicrystal arrays is theoretically proposed for high-quality light wave propagation with high polarization maintaining performance and low nonlinearity. This fiber, called hollow-core photonic quasicrystal fiber (HC-PQF), can simultaneously realize a high birefringence that reaches 1.345 × 10−2 and a small nonlinear coefficient of 1.63 × 10−3 W−1·km−1 at a communication wavelength of 1.55 μm due to the air-filled core and unique quasiperiodic fiber structure. To further demonstrate the controllability of the nonlinear coefficient and the application of sensor and polarization-maintaining fiber, the nonlinearity is investigated by filling different inert gases in the fiber core while the birefringence keeps a high order of 10−2. In the wavelength range λ ∈ [1.53 μm, 1.57 μm], the dispersion is near zero and flattened. The HC-PQF is expected to be used for applications in optical communication, high power pulse transmission, polarization beam splitters, etc.

Lithography-free IR polarization converters via orthogonal in-plane phonons in α-MoO3 flakes.

Abstract: Exploiting polaritons in natural vdW materials has been successful in achieving extreme light confinement and low-loss optical devices and enabling simplified device integration. Recently, α-MoO3 has been reported as a semiconducting biaxial vdW material capable of sustaining naturally orthogonal in-plane phonon polariton modes in IR. In this study, we investigate the polarization-dependent optical characteristics of cavities formed using α-MoO3 to extend the degrees of freedom in the design of IR photonic components exploiting the in-plane anisotropy of this material. Polarization-dependent absorption over 80% in a multilayer Fabry-Perot structure with α-MoO3 is reported without the need for nanoscale fabrication on the α-MoO3. We observe coupling between the α-MoO3 optical phonons and the Fabry-Perot cavity resonances. Using cross-polarized reflectance spectroscopy we show that the strong birefringence results in 15% of the total power converted into the orthogonal polarization with respect to incident wave. These findings can open new avenues in the quest for polarization filters and low-loss, integrated planar IR photonics and in dictating polarization control. Here, the authors investigate the polarization-dependent optical characteristics of cavities formed using α-MoO3 to extend the degrees of freedom in the design of IR photonic components exploiting the in-plane anisotropy of this material. Absorption over 80% and polarization conversion is reported without the need for nanoscale fabrication.

New Alkaline-Earth Metal Fluoroiodates ExhibitingLarge Birefringence and Short Ultraviolet Cutoff Edge with HighlyPolarizable (IO 3 F) 2– Units

Abstract: By the selective fluorination of IO4 in iodates, SrI2O5F2 (SIOF) and Ba­(IO2F2)2 (BIOF) were synthesized successfully. They are the first reported cases of alkaline-earth metal fluoroiodates, and the (IO3F)2– units in SIOF were discovered for the first time to the best of our knowledge. BIOF possesses the shortest UV cutoff edge (230 nm), and SIOF has the largest birefringence (cal. 0.203 at 532 nm) among the reported fluoroiodates. The highly polarizable (IO3F)2–, with high polarizability anisotropy, induces a large birefringence in SIOF by theoretical calculation. This work will contribute to enlarge the structural diversity and provide a good choice for the material design in fluoroiodates.

RbNa(HC3N3O3)·2H2O exhibiting a strong second harmonic generation response and large birefringence as a new potential UV nonlinear optical material

Abstract: A new mixed alkali hydro-isocyanurate, RbNa(HC3N3O3)·2H2O, with the noncentrosymmetric space group Pna21 (No. 33), has been successfully grown by a hydrothermal method. The structure can be described as 2D wavy [Na(HC3N3O3)O4]∞ layers separated by Rb atoms. The UV-vis diffuse reflection measurement revealed that RbNa(HC3N3O3)·2H2O has a large band gap of 5.10 eV, corresponding to the UV cutoff edge of 241 nm. The polarizing microscope measurement of a micron-sized single crystal shows that RbNa(HC3N3O3)·2H2O has a large birefringence of 0.194. The powder SHG measurement indicated that RbNa(HC3N3O3)·2H2O exhibits a strong SHG effect that is 5.3 times that of KH2PO4 (KDP) and can realize phase-matching in the visible and UV region. Moreover, the differences in the SHG responses between RbNa(HC3N3O3)·2H2O and two isostructural compounds have been investigated, which depend heavily on the structural modulation of the (HC3N3O3)2− group by cations. Meanwhile, the electronic structures and optical properties were well analyzed using DFT methods.

Hexagonal In 2 Se 3 : A Defect Wurtzite-Type Infrared Nonlinear Optical Material with Moderate Birefringence Contributed by Unique InSe 5 Unit.

Abstract: The balance between second harmonic generation (SHG) intensity and laser-induced damage threshold (LIDT), together with phase-matchable behavior, is the key point for exploration of novel nonlinear...

Design of a liquid sensing photonic crystal fiber with high sensitivity, bireferingence & low confinement loss

Abstract: This paper represents a Photonic Crystal Fiber (PCF) based sensor structure with concurrently high sensitivity, high birefringence and low confinement loss for liquid sensing applications. We explored the efficiency of the constructed PCFs for Water to be sensed as a liquid sample. The numerical analysis of the proposed structure is performed using the full Finite Element Method (FEM). To minimize the fabrication complexity, circular air holes have been chosen instead of elliptical holes in the core region. The substantial analysis is described at a broad spectrum of wavelengths (1.3 μm–2 μm) and the effect of different design parameters of proposed structures has been studied very sincerely. According to FEM numerical results, the designed PCF sensor offers considerable performance in terms of sensitivity is 49.13% as well as birefringence is 0.008. The suggested framework can be used extremely in the area of bio-sensing studies and commercial applications.

Design of a fabrication friendly & highly sensitive surface plasmon resonance-based photonic crystal fiber biosensor

Abstract: We proffer in this research a distinctive, facile to fabricate, and highly sensitive photonic crystal fiber (PCF) biosensor based on the phenomenon of surface plasmon resonance (SPR). Our prototype has a strategic pattern of circular air holes inside the fiber, which leads to a superior sensing performance. The evaluation of all the sensor characteristics has been discharged by employing the finite element method (FEM) of COMSOL Multiphysics. The gold (Au) layer just around the fiber acts as the plasmonic material, and the TiO2 increases the adhesivity of the gold layer and the fiber. After the optimization of all the fiber parameters, we derived a maximum amplitude sensitivity (AS) and wavelength sensitivity (WS) of 5060 RIU−1 and 41500 nm/RIU, respectively, with a maximum sensor resolution 2.41 × 10−6 for wavelength and 1.98 × 10−6 for amplitude. Moreover, the maximum figure of merit (FOM) procured was 1068.7, and the maximum birefringence was found to be 1.568 × 10−3. The overall analyte sensing range is from refractive indices 1.32 to 1.43, and the sensor has a fabrication tolerance limit of ±10%. Additionally, our sensor's temperature and strain sensitivities are estimated to be 0.75 nm/°C and 3 pm/µe, respectively along with a resolution (temperature) of 1.33 × 10−1 °C. With its enhanced performance in terms of sensitivity, we believe that this SPR based PCF biosensor can potentially contribute to the detection of the unknown analytes and in applications of medical diagnostics.

Deep Learning-Based Holographic Polarization Microscopy.

Abstract: Polarized light microscopy provides high contrast to birefringent specimen and is widely used as a diagnostic tool in pathology. However, polarization microscopy systems typically operate by analyzing images collected from two or more light paths in different states of polarization, which lead to relatively complex optical designs, high system costs, or experienced technicians being required. Here, we present a deep learning-based holographic polarization microscope that is capable of obtaining quantitative birefringence retardance and orientation information of specimen from a phase-recovered hologram, while only requiring the addition of one polarizer/analyzer pair to an inline lensfree holographic imaging system. Using a deep neural network, the reconstructed holographic images from a single state of polarization can be transformed into images equivalent to those captured using a single-shot computational polarized light microscope (SCPLM). Our analysis shows that a trained deep neural network can extract the birefringence information using both the sample specific morphological features as well as the holographic amplitude and phase distribution. To demonstrate the efficacy of this method, we tested it by imaging various birefringent samples including, for example, monosodium urate and triamcinolone acetonide crystals. Our method achieves similar results to SCPLM both qualitatively and quantitatively, and due to its simpler optical design and significantly larger field-of-view this method has the potential to expand the access to polarization microscopy and its use for medical diagnosis in resource limited settings.

Electrically Tunable Multicolored Filter Using Birefringent Plasmonic Resonators and Liquid Crystals

Abstract: Dynamic tuning of color filters finds numerous applications including displays or image sensors. Plasmonic resonators are subwavelength nanostructures which can tailor the phase, polarization, and ...