Phase Retrieval of Vortices in Bose-Einstein Condensates

TL;DR

This paper introduces a numerical measurement scheme to fully reconstruct the 2D quantum wave function of Bose-Einstein condensates, including amplitude and phase, overcoming fundamental ambiguities in phase measurement of vortices.

Contribution

It presents a novel method for complete wave function reconstruction from time-of-flight data, addressing phase ambiguity issues in vortex imaging.

Findings

Successfully reconstructs matter-wave vortices and vortex arrays

Identifies and overcomes phase measurement ambiguities

Demonstrates effectiveness through numerical simulations

Abstract

We propose and demonstrate numerically a measurement scheme for complete reconstruction of the 2D quantum wave function of a Bose-Einstein condensate, amplitude and phase, from a time-of-flight measurement. We identify a fundamental ambiguity present in the measurement of phase structures of high-symmetry excitations (e.g., vortices) and show how to overcome it by allowing for different expansion durations in different directions. We demonstrate this approach with the reconstruction of matter-wave vortices and arrays of vortices.