s-wave scattering lengths of the strongly dipolar bosons $^{162}$Dy and $^{164}$Dy

TL;DR

This study measures the s-wave scattering lengths of two dysprosium isotopes using ultracold gases and compares the results with Boltzmann equation simulations to understand dipolar interactions.

Contribution

First measurement of the triplet s-wave scattering lengths for $^{162}$Dy and $^{164}$Dy using cross-dimensional relaxation and DSMC simulations.

Findings

$a=122(10)a_0$ for $^{162}$Dy

$a=92(8)a_0$ for $^{164}$Dy

Agreement between experimental data and dipolar scattering models

Abstract

We report the measurement of the triplet s-partial-wave scattering length $a$ of two bosonic isotopes of the highly magnetic element, dysprosium: $a=122(10)a_0$ for $^{162}$Dy and $a=92(8)a_0$ for $^{164}$Dy, where $a_0$ is the Bohr radius. The scattering lengths are determined by the cross-dimensional relaxation of ultracold gases of these Dy isotopes at temperatures above quantum degeneracy. In this temperature regime, the measured rethermalization dynamics can be compared to simulations of the Boltzmann equation using a direct-simulation Monte Carlo (DSMC) method employing the anisotropic differential scattering cross section of dipolar particles.