Time-domain simulation of charged particle diffraction by an electrostatically biased grating: Transmission tunability and shaping of the quantum point contact for protons

A numerical simulation of a two-dimensional Gaussian wave packet of charged particles has been performed to investigate the diffraction phenomena from a single-, double-, and multi-slit grating biased with an electrostatic potential ( V-e0). The wave packet dynamics are obtained by solving the time-dependent Schrodinger's equation using the generalized finite difference time domain (GFDTD-Q) method for quantum systems. The effect of V-e0 on transmission properties, fringe pattern, motion of the peaks, and wave number distribution in the diffracted wave has been studied. It is found that V-e0 changes the shape of the quantum point contact of diffracting constriction, which controls the allowed quantum states in the diffracted wave and the transmission coefficient T-c can be tuned by V-e0. It is observed that the number of peaks, their relative intensity, and quantization of lateral wavenumber depend upon V-e0. This study will be helpful in optimizing the parameters for material grating-based matter-wave interferometers employing charged particle such as proton beams. Published under an exclusive license by AIP Publishing.

Automated summary

A numerical simulation of a two-dimensional Gaussian wave packet of charged particles has been performed to investigate the diffraction phenomena from a single-, double-, and multi-slit grating biased with an electrostatic potential. The effect of the potential on transmission properties, fringe pattern, motion of the peaks, and wave number distribution in the diffracted wave has been studied.