Fringe spacing and phase of interfering matter waves

TL;DR

This paper experimentally studies how radio-frequency fields influence the interference patterns of atoms from Bose-Einstein condensates, revealing that fringe spacing depends on rf energy difference and phase control affects matter wave interference.

Contribution

It demonstrates the control of matter wave interference phase and fringe spacing through rf field parameters, providing new insights into atom interferometry.

Findings

Fringe spacing depends on rf energy difference, not gravity.

Rf phase and polarization directly control interference phase.

Provides a semi-classical interpretation of the interference phenomena.

Abstract

We experimentally investigate the outcoupling of atoms from Bose-Einstein condensates using two radio-frequency (rf) fields in the presence of gravity. We show that the fringe separation in the resulting interference pattern derives entirely from the energy difference between the two rf fields and not the gravitational potential difference. We subsequently demonstrate how the phase and polarisation of the rf radiation directly control the phase of the matter wave interference and provide a semi-classical interpretation of the results.