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To the Theory of the Polarized Radiation Absorption in a Semiconductor (001) Quantum Well
摘要： The paper considers absorption of linearly polarized radiation in a semiconductor size-quantized well related to optical transitions both between the branches of light and heavy holes and between the size-quantized subbands. Main features of the light absorption in an infinitely deep symmetric well are elucidated. These features are characterized by intraband absorption of light and associated with the direct optical transitions of holes between the subbands of the semiconductor valence band formed due to the size quantization.
关键词： optical transition,semiconductor,size quantization,light absorption coefficient,polarized light,holes
更新于2025-09-23 15:23:52
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CsPbBr3 nanowire polarized light-emitting diodes through mechanical rubbing
摘要： Anisotropic films composed of aligned CsPbBr3 nanowires (NWs) have been successfully fabricated using a mechanical rubbing method. The films with dense and uniform morphology show polarization photoluminescence (PL) behavior. Combining with an optimal device structure, a polarized light-emitting diode (LED) with a turn-on voltage as low as 6.5 V was achieved.
关键词： CsPbBr3 nanowires,anisotropic films,mechanical rubbing,polarized light-emitting diode,photoluminescence
更新于2025-09-23 15:21:01
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Guanosine Assembly Enabled Gold Nanorods with Dual Thermo- and Photoswitchable Plasmonic Chiroptical Activity
摘要： Noble metal nanostructures with plasmonic circular dichroism (PCD) have attracted interest and a modulation of PCD is of great importance for their potential applications. Herein, we propose a supramolecular strategy for achieving dual thermal and photo-switchable PCD. When guanosine (G), deoxyguanosine (dG) and boric acid modified achiral gold nanorods (GNRs) were co-assembled into hydrogel, hybrid nanofibers with PCD were produced. When the hydrogel was heated, the nanofiber was disassembled and the PCD disappeared. Since the hydrogel was thermally reversible, a thermo-controlled PCD could be realized. The hybrid hydrogel also showed photo-switchable PCD. When the gel was irradiated with IR laser, the PCD disappeared. It can be restored by placing at room temperature. Moreover, the hybrid gel was selectively response to the circularly polarized light (CPL). For (G/dG)-GNRs hybrid assemblies, the R-CPL irradiation showed higher photothermal efficiency than that of L-CPL, which made it useful for an IR-irradiation controlled release of drug molecules.
关键词： plasmonic chirality,gold nanorods,guanosine,circular polarized light,selective response
更新于2025-09-23 15:21:01
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Electromagnetic curves of the polarized light wave along the optical fiber in De-Sitter 2-space $${\mathbb{S}}_{1}^{2}$$S12
摘要： We review the geometric evolution of a linearly polarized light wave coupling into an optical fiber and the rotation of the polarization plane in De-Sitter 2-space. The optical fiber is assumed to be a one-dimensional object imbedded in the De-Sitter 2-space S2 1 is described to be a 2-sphere in a Lorentzian space with positive curvature. Thus, in the De-Sitter 2-space, we have demonstrated that the evolution of a linearly polarized light wave is associated with the Berry phase or more commonly known as the geometric phase. The ordinary condition for parallel transportation is defined by the Fermi–Walker parallelism law. We define other Fermi–Walker parallel transportation laws and connect them with the famous Rytov parallel transportation law for an electric field E, which is considered as the direction of the state of the linearly polarized light wave traveling through the optical fiber in De-Sitter 2-space. Later, we have defined a special class of magnetic curves called by Lorentzian spherical electromagnetic curves (LSEM curves), which are generated by the electric field E along with the linearly polarized monochromatic light wave propagating in the optical fiber. In this way, not only we are able to define a special class of linearly polarized point particles corresponding to LSEM-curves of the electromagnetic field along with the optical fiber in the De-Sitter 2-space, but we can also calculate, both numerically and analytically, the electromagnetic force, Poynting vector, energy-exchanges rate, optical angular and linear momentum, and optical magnetic torque experienced by the linearly polarizable point particles along with the optical fiber in the De-Sitter 2-space.
关键词： Magnetic force,Polarized light wave,Electromagnetic force,Optical angular momentum,Electromagnetic curves,Geometric phase
更新于2025-09-23 15:21:01
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A different view: sensory drive in the polarized-light realm
摘要： Sensory drive, the concept that sensory systems primarily evolve under the in?uence of environmental features and that animal signals are evolutionarily shaped and tuned by these previously existing sensory systems, has been thoroughly studied regarding visual signals across many animals. Much of this work has focused on spectral aspects of vision and signals. Here, I review work on polarized-light signals of animals and relate these to what is known of polarization visual systems, polarized-light aspects of visual scenes, and polarization-related behavior (e.g., orientation, habitat-?nding, contrast enhancement). Other than the broad patterns of scattered polarized light in the sky, most polarization in both terrestrial and aquatic environments results from either re?ection or scattering in the horizontal plane. With overhead illumination, horizontal features such as the surfaces of many leaves or of air: water interfaces re?ect horizontal polarization, and water scatters horizontally polarized light under most conditions. Several animal species have been demonstrated to use horizontally polarized light ?elds or features in critical aspects of their biology. Signi?cantly, most biological signals are also horizontally polarized. Here, I present relevant polarization-related behavior and discuss the hypothesis that sensory drive has evolutionarily in?uenced the structure of polarization signals. The paper also considers the evolutionary origin of circular polarization vision and circularly polarized signals. It appears that this class of signals did not evolve under the in?uence of sensory drive. The study of signals based on polarized light is becoming a mature ?eld of research.
关键词： vision,visual signal,polarized light,sensory drive,animal communication
更新于2025-09-23 15:21:01
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Asymmetric photoelectron emission from chiral molecules using a high repetition rate laser
摘要： In the chiro-optical phenomenon known as photoelectron circular dichroism, the angular distribution of electrons ionized from chiral molecules by circularly polarized light pulses has been found to be anti-symmetric with respect to the direction of the light propagation. To study this phenomenon, chiral molecules were multiphoton ionized with a femtosecond laser in our laboratory. Using a simple stereo-detection setup, direct measurements of the asymmetry for the exemplar aromatic chiral molecule 1-phenylethanol were made using 260 nm pulses produced at a rate of 1 MHz. It was found that the asymmetry had a linear dependence on Stokes’ S3 parameter indicating that the photoelectron circular dichroism is due to a single photon process from the excited state of the molecule. This is in contrast to previous and new results for camphor where a more complex dependence on S3 suggested that selective excitation of molecules with certain orientations was influential.
关键词： photoelectron circular dichroism,circularly polarized light,asymmetry,Stokes’ S3 parameter,chiral molecules
更新于2025-09-23 15:19:57
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Quantum dots power polarizing light source
摘要： A new way of generating linearly polarized photons using quantum dots has been developed by an international team of researchers. The novel source of polarized light could be used to develop energy-saving computers and mobile-phone screens, as well as secure communications. Researchers have long studied quantum dots and their many possible applications, but getting them to emit photons that have a predefined polarization has proved difficult and this is an essential requirement for many applications.
关键词： quantum dots,polarized light,InGaN,gallium-nitride pyramids,indium gallium nitride
更新于2025-09-23 15:19:57
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Multiport optical power splitter design based on coupled-mode theory
摘要： We proposed a multiport T-shaped 1 x 8 balanced optical power splitter design based on asymmetric vertical silicon slot waveguides working on the principle of coupled-mode theory (CMT). The scheme of the power splitter is unique which offers strong field confinement of TE-polarized light and delivers the light to four ports each on two opposite side of the chip. By shifting the slot towards the outer sideline of the bend, the bending losses are reduced to 80% as compared to standard symmetric slot waveguide.
关键词： coupled-mode theory,asymmetric vertical silicon slot waveguides,bending losses,TE-polarized light,optical power splitter
更新于2025-09-23 15:19:57
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Inorganic photovoltaic cells based on BiFeO <sub/>3</sub> : spontaneous polarization, lattice matching, light polarization and their relationship to photovoltaic performance
摘要： Inorganic ferroelectric perovskite oxides are more stable than hybrid perovskites. However, their solar energy harvest efficiency is not so good. Here, by constructing a series of BiFeO3-based devices (solar cells), we investigated three factors that influence the photovoltaic performance, including spontaneous polarization, terminated ions species in the interface between BiFeO3 and the electrode, and polarized light irradiation. This work was carried out in the framework of density functional theory combined with non-equilibrium Green’s function theory under built-in electric field or finite bias. The results showed that 1) the photocurrent is larger only under a suitable electronic band gap rather than larger spontaneous polarization; 2) the photocurrent reaches the largest in Bi3+ ions terminated interface than in the case of Fe3+ or O2- with SrTiO3 electrode; 3) the photocurrent could be largely enhanced if the polarized direction of the monochromatic light is perpendicular to the spontaneous polarization direction. The results would deepen the understanding of some experimental results of BiFeO3-based solar cells.
关键词： BiFeO3,solar cells,spontaneous polarization,polarized light,photovoltaic performance
更新于2025-09-23 15:19:57
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Enhanced light-emitting diode induced fluorescence detection system with capillary electrophoresis
摘要： An enhanced fluorescence detection system of capillary electrophoresis (CE) was equipped with a concave silver mirror, by which the detection sensitivity of light-emitting diode induced fluorescence (LEDIF) can be increased greatly. The silver concave mirror and the cathode window in photomultiplier tube (PMT) were accurately set face to face at the same axis. When the two labeled tumor markers exactly moved to the center of detection window, the emission from analytes are excitated by LED source. Currently, the analytes may be regarded as a luminescent source point. When the source point exactly moves to the focus of the concave mirror, the emission of the labeled sample was collected effectively, enhanced by convergence and reflected by the concave mirror. Then it was sensitively detected by the PMT. The optical mechanism of enhancing detection sensitivity was explored. A simple comparative test on sensitivity was carried out, which aimed to compare sensitivity of the new detection system with concave mirror to that without concave mirror but the other conditions were kept the same. Two tumor markers labeled with FITC were selected for the test, using the simple LEDIF detect system. The results (LOD, 150 nM for L-Leu and L-Val) showed that the detection sensitivity matched with concave mirror reached more 16 times than the detection method without concave mirror.
关键词： Curvature radius,Light-emitting diode induced fluorescence,Tumor markers,Concave silver mirror,Polarized light,Highly sensitive optical detector
更新于2025-09-19 17:13:59