Realization of a Townes soliton in a two-component planar Bose gas

TL;DR

This paper demonstrates the creation of a Townes soliton in a two-component Bose gas, confirming its scale-invariant properties and expanding understanding of two-dimensional soliton stability.

Contribution

It presents a method to deterministically realize a Townes soliton in a 2D Bose gas using internal state transfer, highlighting scale invariance across different sizes.

Findings

Confirmed solitonic behavior at specific interaction strength and atom number

Demonstrated scale invariance of the Townes soliton

Expanded experimental realization of 2D solitons in Bose gases

Abstract

Most experimental observations of solitons are limited to one-dimensional (1D) situations, where they are naturally stable. For instance, in 1D cold Bose gases, they exist for any attractive interaction strength $g$ and particle number $N$. By contrast, in two dimensions, solitons appear only for discrete values of $gN$, the so-called Townes soliton being the most celebrated example. Here, we use a two-component Bose gas to prepare deterministically such a soliton: Starting from a uniform bath of atoms in a given internal state, we imprint the soliton wave function using an optical transfer to another state. We explore various interaction strengths, atom numbers and sizes, and confirm the existence of a solitonic behaviour for a specific value of $gN$ and arbitrary sizes, a hallmark of scale invariance.