Massive particle interferometry with lattice solitons: robustness against ionization

TL;DR

This paper explores the robustness of lattice soliton interferometry against ionization, demonstrating that interference fringes persist even when the soliton's kinetic energy exceeds the dissociation threshold, thus relaxing previous elastic scattering assumptions.

Contribution

It introduces an interferometric scheme for lattice solitons and shows through numerical simulation that coherence is maintained beyond elastic scattering conditions.

Findings

Interferometric fringes persist despite ionization.

Coherence between reflected and transmitted parts is detectable.

Robustness of soliton-based interferometry against ionization.

Abstract

We revisit the proposal of Castin and Weiss [Phys. Rev. Lett. vol. 102, 010403 (2009)] for using the scattering of a quantum matter-wave soliton on a barrier in order to create a coherent superposition state of the soliton being entirely to the left of the barrier and being entirely to the right of the barrier. In that proposal, is was assumed that the scattering is perfectly elastic, i.e. that the center-of-mass kinetic energy of the soliton is lower than the chemical potential of the soliton. Here we relax this assumption. Also, we introduce an interferometric scheme, which uses interference of soltions, that can be used to detect the degree of coherence between the reflected and transmitted part of the soliton. Using exact diagonalization, we numerically simulate a complete interferometric cycle for a soliton consisting of six atoms. We find that the interferometric fringes persist even when the center-of-mass kinetic energy of the soliton is above the energy needed for complete dissociation of the soliton into constituent atoms.