# Non-linear stationary solutions in realistic models for analog black-hole lasers

## TL;DR

This paper proposes realistic models for black-hole lasers in Bose-Einstein condensates, demonstrating how to create large supersonic regions and analyzing stationary states using experimentally feasible setups.

## Contribution

It introduces experimentally implementable models for black-hole lasers, extending configurations symmetrically to achieve large supersonic regions and analyzing their stationary states.

## Key findings

- Black-hole laser configurations can be symmetrically extended to have arbitrarily large supersonic regions.
- Proposed models include an attractive square well and a double delta-barrier for experimental realization.
- Identified the true ground state and discussed dynamical instabilities in these setups.

## Abstract

From both a theoretical and an experimental point of view, Bose-Einstein condensates are good candidates for studying gravitational analogues of black holes and black-hole lasers. In particular, a recent experiment has shown that a black-hole laser configuration can be created in the laboratory. However, the most considered theoretical models for analog black-hole lasers are quite difficult to implement experimentally. In order to fill this gap, we devote this work to present more realistic models for black-hole lasers. For that purpose, we first prove that, by symmetrically extending every black-hole configuration, one can obtain a black-hole laser configuration with an arbitrarily large supersonic region. Based on this result, we propose the use of an attractive square well and a double delta-barrier, which can be implemented using standard experimental tools, for studying black-hole lasers. We also compute the different stationary states of these setups, identifying the true ground state of the system and discussing the relation between the obtained solutions and the appearance of dynamical instabilities.