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A three-port surface-relief grating with a connecting layer under the second Bragg condition is put forward and designed for the free space application in this paper. Such grating can function as a beam splitter, which can split the polarized light into the − 2nd order and the − 1st order and the 0th order based on the optimum grating profile parameters. By using rigorous coupled-wave analysis, a highly-efficient polarization-dependent connecting-layer-based grating can be obtained with the optimum different depths and thicknesses with the grating duty cycle of 0.65 and grating period of 1150 nm. On the basis of the designed grating profile parameters, a modal method can explain the propagating process. Compared with the conventional surface-relief fused-silica grating, the diffraction efficiencies for TE polarization in three orders are improved. Therefore, the novel conception of the grating under the second Bragg condition is significant for further applications such as interferometer with improved efficiency for TE polarization. [ABSTRACT FROM AUTHOR]

In this paper, localized surface plasmon resonance (LSPR) of periodic two-dimensional (2D) gold nanoparticles arrays is investigated using far field polarization spectroscopy. Square and rectangular arrays of 60 nm gold nanoparticles with different interparticle spacings are fabricated with electron beam lithography (EBL). The experimental extinction cross section spectra are revealed the existence of two plasmon modes depending to the polarization direction of the incident radiation on the sample. The extinction spectra are calculated using coupled dipole approximation (CDA). Good qualitative and quantitative agreement is obtained between calculations and experimental results. Moreover, it is found that the interparticle spacing on the array was the key parameter to study the plasmon interaction between the nanoparticles and to determine the amplitude, spectral position and width of LSPR band. [ABSTRACT FROM AUTHOR]

The polarization dependence of the photosensitivity (PS) of the Schottky barrier photodiodes based on the InGaAs/GaAs quantum well (QW) structures has been studied using the in-plane photoexcitation of the QW by linearly-polarized light through a cleaved facet. The interband optical transitions involving the quantum confined heavy-hole (hh) and the light hole (lh) states were identified in the PS spectra by their different polarization dependences. The latter follow the theoretical ones for the absorption coefficient with good agreement. The effect of lifting of the polarization selection rules in the QW due to the hh and lh mixing at the QW heterointerface has been studied both theoretically and experimentally. The importance of taking this effect into account in analysis of the PS polarization dependence in the excited state transition bands has been shown. [ABSTRACT FROM AUTHOR]