Quantum reflection of rare gas atoms and molecules from a grating

TL;DR

This paper provides a theoretical simulation of quantum reflection of rare gas atoms and molecules from a grating, confirming universal behavior dependent on de Broglie wavelength and revealing particle-specific angular reflection efficiencies.

Contribution

It offers the first detailed theoretical analysis of quantum reflection from gratings, highlighting the dependence on particle identity and surface interactions.

Findings

Threshold angles depend solely on de Broglie wavelength.

Reflection efficiency varies with incident particle.

Surface interaction details influence quantum reflection.

Abstract

Quantum reflection is a universal property of atoms and molecules when scattered from surfaces in ultracold collisions. Recent experimental work has documented the quantum reflection and diffraction of He atoms, dimers, trimers and Neon atoms when reflected from a grating. Conditions for the observation of emerging beam resonances have been discussed and measured. In this paper, we provide a theoretical simulation of the quantum reflection in these cases from a grating. We confirm, as expected the universal dependence on the incident de Broglie wavelength only of the threshold angles for the observation of emerging beam resonances. However, the angular dependence of the reflection efficiencies, that is the ratio of scattered intensity into specific diffraction channels relative to the total intensity is found to be dependent on the specifics of the incident particle. The dependence of the reflection efficiency on the identity of the particle is intimately related to the fact that the incident energy dependence of quantum reflection depends on the details of the particle surface interaction.