Molecular Design,Circularly Polarized Luminescence,and Helical Self‐Assembly of Chiral Aggregation‐Induced Emission Molecules

Aggregation‐induced emission luminogens (AIEgens) are a new class of luminophors, which are non‐emissive in solution, but emit intensively upon aggregation. By properly designing the chemical structures of the AIEgens, their aggregation process can be tuned towards a desired direction to give diverse novel luminescent architectures of micelles, rods, and helical fibers. AIEgens represent a kind of promising building block for the fabrication of luminescent micro/nanostructures with controllable morphologies. In this review, we describe our recent work in this research area, focusing on the molecular design, circularly polarized luminescence properties, and helical self‐assembly behavior of AIEgens.     

Circularly Polarized Absorption Property of Tetra-4[4''''-(2-methylbutoxy)benzoyloxy]phenyl Porphyrin by Introducing Optical Pendant Groups

Circularly polarized luminescent(CPL) materials possess special dissymmetric optical property, i.e. luminescent light having different intensities for left (L) and right(R) circularly polarized components. Recently, these materials have been applied in colour-image projection, stereoscopic displays and light-emitting diodes(LEDS)1-7. We have synthesized a new porphyrin derivative, tetra-4[4'-(2-methylbutoxy)benzoyloxy] phenyl porphyrin [T(MBBP)P], by introducing a chiral group, which p…     

Relativity versus the longitudinal magnetic field of the photon

The longitudinal magnetic field ascribed by Evans to a circularly polarized electromagnetic wave is discussed. It is proved that this theory is inconsistent with special relativity.     

Photon emission from non-oriented spin systems

A method is suggested to determine experimentally whether the state of a spin system is oriented or non-oriented by measuring the angular distribution,I and the circular polarization asymmetry,A _c of the photons emitted by the system. These also provide enough data to determine the density matrix completely.     

Quantum nanostructures of paraelectric PbTe

This article provides a review of our results on nanostructurization of lead telluride, PbTe. This IV–VI group narrow-gap semiconductor exhibits paraelectric behaviour leading to a huge dielectric constant ε>1000 at helium temperatures. Because the Coulomb potential fluctuations produced by charged defects are strongly suppressed in PbTe nanostructures, one can reach the quantum ballistic regime at significantly relaxed conditions in comparison with other systems. In particular, we observe precise zero-field conductance quantization in the wires made of modulation doped PbTe/PbEuTe quantum wells where the heavily doped layer is separated from the conducting channel only by a 2 nm thick spacer layer. The second important property is the very large Zeeman splitting. It reaches 4 meV/T. Accordingly, significant spin splitting of the conductance plateaux is observed already at fields below 1 T. Therefore, the system is attractive for the construction of local spin filters. We show that the presence of metal layers does not impair the quantum ballistic properties. Furthermore, we have developed a new method of tuning the PbTe nanostructures, using laterally placed metallic electrodes. We have found that this method is more effective than previous schemes using used p–n junctions and it provides better stability of the nanostructures.     

Spin-Hall transport in a two-dimensional electron system with magnetic impurities

The spin Hall transport properties in a two-dimensional electron system with both Rashba spin-orbit coupling (SOC) and magnetic impurities are investigated. Electrons are scattered by impurities through an exchange interaction that leads to spin flip-flop processes and so changes the spin Hall effect induced by the SOC. The spin Hall conductance is calculated in a 4-terminal system using the Landauer-Buttiker formula and Green function approach. In comparison with the simulation results on nonmagnetic impurities doping systems, our results reveal that the spin Hall conductance is still nonzero in a system with a large density of magnetic impurities and a finite intensity of the exchange interaction between the electrons and impurities, and its sign may be altered when the doping density and interaction strength are large enough.     

偏光眼镜的理论及应用

本文就偏光眼镜的制造、理论及应用前景作了一些介绍。从长远来看，选择更好的偏振材料不仅对偏光眼镜，而且对许多偏光仪器也有重大意义。     

Monte Carlo study of time asymptotics of the polarized radiation intensity

The parameters of time asymptotics of the polarized radiation intensity are estimated. Precision Monte Carlo estimates of these parameters are derived for finite medium layers by iterating the resolvent of the corresponding transfer operator with a given scattering matrix and by evaluating parametric time derivatives. The computations are performed for two versions of the problem: with a Rayleigh scattering matrix and an aerosol scattering matrix. It is shown that the asymptotics of the radiation intensity are affected by polarization, except for the spatially homogeneous problem, for which the results are obtained analytically.     

Photoelectric Properties of p-GaSe/n-CdGa2S4 Heterostructures

Single crystals of the ternary compound CdGa₂S₄ have been grown from the melt by the Bridgman–Stockbarger method and their composition, structure, and electrophysical properties have been determined. From the crystals obtained, p-GaSe/n-CdGa₂S₄ heterostructures have been generated for the first time and their photoelectric properties in natural and linearly polarized light have been investigated. We determine the main parameters of the heterostructures and show that they can be used in photoprocessors of optical radiation.     

Calculation of the Band Intensities of the IR Spectra of Oriented Polymers

An attempt has been made to extend the theory of IR spectra of polymers to oriented polymers. Formulas for the absorption-band intensities in polarization IR spectra of oriented polymers reflecting the dependence of the polarized absorption-band intensity on the structural and orientation characteristics of polymers have been obtained. These formulas permit calculating the intensity of polarized absorption bands at different degrees of orientation of the polymer.