Stack-based grating for wideband polarization splitter in terahertz

Abstract

A novel wideband terahertz polarization beam splitter with special diffraction orders working at terahertz band is described in this paper. The polarizer can achieve high diffraction efficiency and uniformity in the 2.50 - 2.56 THz band. Based on rigorous coupled-wave analysis (RCWA) and simulated annealing algorithm, we proposed an efficient algorithm to optimize the polarizer. After calculations, 98.45% single-port high-efficiency reflection for transverse electric (TE) polarization and 42.33%/42.57% highly uniform dual-port beam splitting for transverse magnetic (TM) polarization were finally obtained. In addition, through RCWA and simplified modal method, the electromagnetic field distributions of TE and TM polarizations are shown visually and described quantitatively. Moreover, the results displayed in Sec. 3 prove that the grating possesses the characteristics of relatively large bandwidth and insensitivity to the incident angle. Therefore, the novel scheme in this paper has great reference value for the research of terahertz modulation devices and the integration of terahertz communication systems.

The third post-Newtonian equatorial motion in Kerr spacetime

“…We follow the iterative method given by Soffel et al [10] and Yang et al [33] to derive the analytical solution for the post-Newtonian motion. The trajectory of the test particle in the equatorial plane of the Kerr black hole can be expressed as…”

Conical holes arrays for 2 × 2 ports division

“…For sub-wavelength grating [27,28], vector diffraction theory [23,29] is usually used in the analysis. The analysis of two-dimensional gratings involves the use of electromagnetic theory, such as calculating the reflection and transmission characteristics of a grating by solving the Maxwell equations.…”

High throughput composite sensor based on sub-wavelength dielectric grating/MDM waveguide/periodic photonic crystal

“…At present, the important forms of light-matter interaction have become a research hotspot in the subwavelength optics, including surface plasmon resonance (SPR) [1][2][3], diffraction effects [4], and coupling resonances [5,6]. They can confine incident optical waves at the subwavelength scale [7] and enhance the local electro-magnetic field, symmetric or asymmetric resonance peaks are obtained in the spectrum.…”