Spatially Modulated Interaction Induced Bound States and Scattering Resonances

TL;DR

This paper investigates how spatially modulated interactions in a two-channel model lead to bound states and scattering resonances, offering new control methods for cold atom experiments with minimal inelastic loss.

Contribution

It introduces a theoretical framework for understanding bound states and scattering resonances induced by spatially modulated interactions in cold atom systems.

Findings

Sequence of bound states appears with increasing modulation amplitude

Divergence of effective scattering length occurs at certain modulations

Local scattering length varies spatially in different regimes

Abstract

We study the two-body problem with a spatially modulated interaction potential using a two-channel model, in which the inter-channel coupling is provided by an optical standing wave and its strength modulates periodically in space. As the modulation amplitudes increases, there will appear a sequence of bound states. Part of them will cause divergence of the effective scattering length, defined through the phase shift in the asymptotic behavior of scattering states. We also discuss how the local scattering length, defined through short-range behavior of scattering states, modulates spatially in different regimes. These results provide a theoretical guideline for new control technique in cold atom toolbox, in particular, for alkali-earth-(like) atoms where the inelastic loss is small.