Ultra sub-wavelength resolution terahertz near-field imaging: modelling via the FDTD method in a multi-pixel sampling approach

Abstract

In this work, the finite difference time domain (FDTD) method is used to optimize the multi-pixel sampling approach, in order to achieve ultra-high spatial resolution (∼ λ/110) in the near-field region. The optimization is performed based on the optical pump pulse wavelength, the thickness of the silicon modulator, and the size of the aperture in the projected pattern. To the best of our knowledge, this is the first time that the FDTD method has been used to improve near-field resolution. In addition, we consider the effect of pump wavelength on near field imaging resolution for the first time.

Intelligent electromagnetic mapping via physics driven and neural networks on frequency selective surfaces

“…As conventional approaches for EM analysis, EM calculation methods, i.e. finite-difference time-domain methods and methods of moments have been extensively researched to reveal the EM characteristics of diverse structures in detail [25][26][27][28][29][30][31][32][33]. However, the solving of Maxwell equations and elaborate mesh division raises high demand for computer hardware.…”

Terahertz Spiral Spatial Filtering Imaging

“…Therefore, developing a new THz imaging method for low-contrast objects is of great importance. As one of the last mastered frequency ranges of the electromagnetic spectrum, the THz band provides great potential for modern imaging methods which have been widely applied in other spectral regions [6][7][8][9][10][11][12][13][14][15]. Notably, THz imaging techniques can be applied in various fields, such as security screening [16,17], non-destructive testing [18][19][20], biological detection [1,21], and data-rata communications [22,23].…”