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We theoretically suggest and experimentally demonstrate a broadband composite optical rotator that is capable of rotating the polarization plane of a linearly-polarized light at any chosen angle. The device is composed of an even ...
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We theoretically suggest and experimentally demonstrate a broadband composite optical rotator that is capable of rotating the polarization plane of a linearly-polarized light at any chosen angle. The device is composed of an even number of half-wave plates (WPs) rotated at specific angles with respect to their fast-polarization axes. The frequency bandwidth of the polarization rotator in principal increases with the number of half-WPs. Here we experimentally examine the performance of rotators composed of two, four, six, eight and ten half-WPs.
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The structural phase transformations of 0.7Pb(Mg1/3Nb2/3)O-3-0.3PbTiO(3) (PMN-30%PT) have been studied using x-ray diffraction (XRD) and neutron scattering as a function of temperature and electric field. We observe the phase tran...
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The structural phase transformations of 0.7Pb(Mg1/3Nb2/3)O-3-0.3PbTiO(3) (PMN-30%PT) have been studied using x-ray diffraction (XRD) and neutron scattering as a function of temperature and electric field. We observe the phase transformational sequence (i) cubic (C)--> tetragonal (T)--> rhombohedral (R) in the zero-field-cooled (ZFC) condition; (ii) C-->T--> monoclinic (M-C)--> monoclinic (M-A) in the field-cooled (FC) condition; and (iii) R-->M-A-->M-C-->T with increasing field at fixed temperature beginning from the ZFC condition. Upon removal of the field, the M-A phase is stable at room temperature in the FC condition, and also in the ZFC condition with increasing field. Several subtleties of our findings are discussed based on results from thermal expansion and dielectric measurements, including (i) the stability of the M-A phase, (ii) a difference in lattice parameters between inside bulk and outside layer regions, and (iii) a difference in the phase transition temperature between XRD and dielectric data. (C) 2004 American Institute of Physics.
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Single-layered metasurfaces are easier to fabricate than multi-layered ones but suffering from low efficiency and/or narrow bandwidth for transmissive polarization rotation. In this work, we propose a single-layered metasurface wh...
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Single-layered metasurfaces are easier to fabricate than multi-layered ones but suffering from low efficiency and/or narrow bandwidth for transmissive polarization rotation. In this work, we propose a single-layered metasurface which can realize 90 degrees polarization rotation with high efficiency, wide bandwidth, and ultra-high polarization conversion ratio in transmission mode. In addition, the single-layered metasurface can also be used as an efficient and wideband polarizer, which couples the two orthogonal electric components of incident light to the transmitted polarization.
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We propose a theoretical study of the influence of temperature on the state of polarization of a near-infrared light beam reflected from or transmitted through a voltage-controlled nematic liquid crystal (LC) cell deposited on a m...
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We propose a theoretical study of the influence of temperature on the state of polarization of a near-infrared light beam reflected from or transmitted through a voltage-controlled nematic liquid crystal (LC) cell deposited on a magnetic film. In both cases, the change in polarization with respect to that of the incoming beam originates in the linear Kerr or Faraday effects taking place in the magnetic layer, but the overall value of the polarization plane rotation depends on the reflectivity and transmittivity of the whole heterostructure. Temperature manifests itself in all layers of the structure through both thermal expansion and the thermo-optic effect when it varies between room temperature and the temperature of nematic-isotropic phase transition in the LC. The thermo-optic effect is strongest in the LC cell, where it is shown to induce noticeable variations of the polarization plane rotation of both reflected and transmitted light beams in that temperature range. Such temperature-dependent changes of the magneto-optical response can be compensated for by adjusting the dc voltage applied to the LC. On the other hand, we show that they may be exploited for sensitive temperature monitoring.
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Polarization rotation engineering is a promising path to giant dielectric and electromechanical responses in ferroelectric materials and devices. This work demonstrates robust and reversible in- to out-of-plane polarization rotati...
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Polarization rotation engineering is a promising path to giant dielectric and electromechanical responses in ferroelectric materials and devices. This work demonstrates robust and reversible in- to out-of-plane polarization rotation in ultrathin (nanoscale) epitaxial (001) tetragonal PbZr_(0.3) Ti_(0.7)O_3 (PZT-T)/rhombohedral PbZr_(0.55)Ti_(0.45)O_3 (PZT-R) ferroelectric bilayers. An underlying 20 nm thick PZT-R layer reduces the symmetry in a 5 nm thick PZT-T layer by imposing an in-plane tensile strain while simultaneously decoupling the PZT-T layer from the substrate. This prevents clamping and facilitates large-scale polarization rotation switching (≈60 μC cm~(?2)) and an effective d 33 response 500% (≈250 pm V~(?1)) larger than the PZT-R layer alone. Furthermore, this enhancement is stable for more than 10~7 electrical switching cycles. These bilayers present a simple and highly controllable means to design and optimize rotational polar systems as an alternate to traditional composition-based approaches. The precise control of the subtle interface-driven interactions between the lattice and the external factors that control polarization opens a new door to enhanced—or completely new—functional properties.
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Knowing and controlling the spatial polarization distribution of a beam is of importance in applications such as optical tweezing, imaging, material processing, and communications. Here we show how the polarization distribution is...
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Knowing and controlling the spatial polarization distribution of a beam is of importance in applications such as optical tweezing, imaging, material processing, and communications. Here we show how the polarization distribution is affected by both linear and nonlinear (self-focusing) propagation.We derive an analytical expression for the polarization rotation of fully structured light (FSL) beams during linear propagation and show that the observed rotation is due entirely to the difference in Gouy phase between the two eigenmodes comprising the FSL beams, in excellent agreement with numerical simulations.We also explore the effect of cross-phase modulation due to a self-focusing (Kerr) nonlinearity and show that polarization rotation can be controlled by changing the eigenmodes of the superposition, and physical parameters such as the beam size, the amount of Kerr nonlinearity, and the input power. Finally, we show that by biasing cylindrical vector beams to have elliptical polarization, we can vary the polarization state from radial through spiral to azimuthal using nonlinear propagation.
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Advantages and disadvantages of taking into account rotation of polarized nuclei in classical trajec-tory calculations of ternary fission are considered. Expressions for polarization of the fissioning deformed com-pound nucleus wh...
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Advantages and disadvantages of taking into account rotation of polarized nuclei in classical trajec-tory calculations of ternary fission are considered. Expressions for polarization of the fissioning deformed com-pound nucleus which allow for the quantum number K in the fission channel are derived.
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This paper describes a simple interferometric arrangement, which allows a direct observation of Berry's topological phase in optical fibers, The interferometer consists of a single mode, low birefringent fiber ring that involves a...
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This paper describes a simple interferometric arrangement, which allows a direct observation of Berry's topological phase in optical fibers, The interferometer consists of a single mode, low birefringent fiber ring that involves a non-coplanar path (a helix). The fringe shift observed by changing the helix pitch permits the measurement of the geometrical phase. [References: 8]
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This article describes full analysis of a novel transverse electric (TE) to transverse magnetic (TM) polarization rotator based on mode interference utilizing finite element method. The core, substrate, and cladding of the polariz...
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This article describes full analysis of a novel transverse electric (TE) to transverse magnetic (TM) polarization rotator based on mode interference utilizing finite element method. The core, substrate, and cladding of the polarization rotator are in the hybrid technology of InGaAsP and SiO2 materials. Effect of several parameters such as core's refractive index, width to height ratio of the polarization rotator, and incident light's wavelength on polarization conversion length, polarization efficiency, polarization extinction ratio, and rotation angle were investigated. Simulation results revealed that the rotation length was less than 1 pm, while the polarization conversion efficiency of 90%, polarization extinction ratio of 15 dB, and maximum rotation angle of 85 at 1.55 m wavelength can be achieved. (C) 2017 Elsevier GmbH. All rights reserved.
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In this work, first the necessary conditions for a versatile cross-polarization conversion meta-atom that operates both for linear and circular cross polarizations are discussed. Based on these, a versatile chiral metasurface cros...
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In this work, first the necessary conditions for a versatile cross-polarization conversion meta-atom that operates both for linear and circular cross polarizations are discussed. Based on these, a versatile chiral metasurface cross-polarization converter is proposed. The correspondence between its physical geometry and polarization domain characteristics is studied. To verify the design concept, a prototype is fabricated and measured. An effective vertical and horizontal linear cross-polarization conversion is achieved from 29.3 to 38.8 GHz (27.90%) and from 34.0 to 36.6 GHz (7.36%), respectively. Furthermore, the proposed converter also achieves circular polarization handedness rotation from 34.5 to 36.6 GHz (5.91%).
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