# Influence of a dark-soliton on the reflection of a Bose-Einstein condensate by a square barrier

## TL;DR

This paper investigates how a dark-soliton within a Bose-Einstein condensate influences its quantum reflection from a square barrier, revealing that the soliton reduces reflection probability and its effects depend on initial orientation.

## Contribution

It demonstrates the impact of dark-solitons on quantum reflection in BECs and explores how initial orientation affects the process, which is a novel insight.

## Key findings

- Dark-solitons decrease the asymptotic reflection probability.
- Reflection probability is highly sensitive to the initial orientation of the dark-soliton.
- Dark-solitons influence excitation properties during condensate-barrier interaction.

## Abstract

We study the quantum reflection of a two-dimensional disk-shaped Bose-Einstein condensate with a dark-soliton excitation by a square potential barrier. For the giving geometry, the dark-soliton initially located at the centre of the condensate cloud survive long enough for investigating the reflection process. We show the time evolution of the reflection probability with respect to various width of the barrier. The asymptotic value of the reflection probability is decreased by the existence of a dark-soliton, and is highly sensitive to the initial orientation of the dark-soliton which also affects the excitation properties during the process of condensate and barrier interaction.