Formation of ultracold $^{39}$K$^{133}$Cs Feshbach molecules

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Beulenkamp, Charly, Zamarski, Krzysztof P., Bird, Robert C., Sueur, C. Ruth Le, Hutson, Jeremy M., Landini, Manuele, Nägerl, Hanns-Christoph
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912607270600704
author Beulenkamp, Charly
Zamarski, Krzysztof P.
Bird, Robert C.
Sueur, C. Ruth Le
Hutson, Jeremy M.
Landini, Manuele
Nägerl, Hanns-Christoph
author_facet Beulenkamp, Charly
Zamarski, Krzysztof P.
Bird, Robert C.
Sueur, C. Ruth Le
Hutson, Jeremy M.
Landini, Manuele
Nägerl, Hanns-Christoph
contents We report the creation of an ultracold gas of bosonic $^{39}$K$^{133}$Cs molecules. We first demonstrate a cooling strategy relying on sympathetic cooling of $^{133}$Cs to produce an ultracold mixture. From this mixture, weakly bound molecules are formed using a Feshbach resonance at 361.7 G. The molecular gas contains $7.6(10)\times 10^3$ molecules with a lifetime of about 130 ms, limited by two-body decay. We perform Feshbach spectroscopy to observe several new interspecies resonances and characterize the bound state used for magnetoassociation. Finally, we fit the combined results to obtain improved K-Cs interaction potentials. This provides a good starting point for the creation of ultracold samples of ground-state $^{39}$K$^{133}$Cs molecules.
format Preprint
id arxiv_https___arxiv_org_abs_2506_16520
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Formation of ultracold $^{39}$K$^{133}$Cs Feshbach molecules
Beulenkamp, Charly
Zamarski, Krzysztof P.
Bird, Robert C.
Sueur, C. Ruth Le
Hutson, Jeremy M.
Landini, Manuele
Nägerl, Hanns-Christoph
Quantum Gases
Atomic Physics
We report the creation of an ultracold gas of bosonic $^{39}$K$^{133}$Cs molecules. We first demonstrate a cooling strategy relying on sympathetic cooling of $^{133}$Cs to produce an ultracold mixture. From this mixture, weakly bound molecules are formed using a Feshbach resonance at 361.7 G. The molecular gas contains $7.6(10)\times 10^3$ molecules with a lifetime of about 130 ms, limited by two-body decay. We perform Feshbach spectroscopy to observe several new interspecies resonances and characterize the bound state used for magnetoassociation. Finally, we fit the combined results to obtain improved K-Cs interaction potentials. This provides a good starting point for the creation of ultracold samples of ground-state $^{39}$K$^{133}$Cs molecules.
title Formation of ultracold $^{39}$K$^{133}$Cs Feshbach molecules
topic Quantum Gases
Atomic Physics
url https://arxiv.org/abs/2506.16520