Massive particle interferometry with lattice solitons

TL;DR

This paper proposes a lattice soliton interferometry scheme using attractive bosons, demonstrating that interference fringes persist even when the soliton's kinetic energy exceeds the dissociation threshold, challenging previous assumptions.

Contribution

It extends prior work by analyzing soliton scattering beyond elastic conditions using Bethe ansatz and DMRG, showing robustness of interference fringes.

Findings

Interference fringes persist at higher kinetic energies.

Soliton coherence is maintained despite partial dissociation.

The scheme is feasible beyond ideal elastic scattering conditions.

Abstract

We discuss an interferometric scheme employing interference of bright solitons formed as specific bound states of attracting bosons on a lattice. 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, it 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: By employing a combination of Bethe ansatz and DMRG based analysis of the dynamics of the appropriate many-body system, we find that the interferometric fringes persist even when the center-of-mass kinetic energy of the soliton is above the energy needed for its complete dissociation into constituent atoms.