# Momentum correlations of a few ultra-cold bosons escaping from an open well

## TL;DR

This paper investigates how the momentum distributions of a few ultra-cold bosons change during escape from an open well, revealing transitions in decay processes and offering insights for experimental studies.

## Contribution

It introduces a detailed analysis of momentum correlations in few-boson escape dynamics, highlighting transition points and generalizing to higher particle numbers.

## Key findings

- Momentum distributions show a transition from pair to sequential tunneling.
- Characteristic spectral features identify specific decay processes.
- Tan's contact dynamics reflect the tunneling transition.

## Abstract

The dynamical properties of a one-dimensional system of two and three bosons escaping from an open potential well are studied in terms of the momentum distributions of particles. In the case of a two-boson system, it is shown that the single- and two-particle momentum distributions undergo a specific transition as the interaction strength is tuned through the point where tunneling switches from the pair tunneling to the sequential one. Characteristic features in the momentum spectra can be used to quantitatively determine the participation of specific decay processes. A corresponding analysis is also performed for the three-boson system, showing a scheme for generalizations to higher particle numbers. For completeness, the time-dependent Tan's contact of the system is also examined and its dynamics is found to undergo a similar transition. The results provide insight into the dynamics of decaying few-body systems and offer potential interest for experimental research.