Observation of Self-Bound Droplets of Ultracold Dipolar Molecules

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Zhang, Siwei, Yuan, Weijun, Bigagli, Niccolò, Kwak, Haneul, Karman, Tijs, Stevenson, Ian, Will, Sebastian
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912611019259904
author Zhang, Siwei
Yuan, Weijun
Bigagli, Niccolò
Kwak, Haneul
Karman, Tijs
Stevenson, Ian
Will, Sebastian
author_facet Zhang, Siwei
Yuan, Weijun
Bigagli, Niccolò
Kwak, Haneul
Karman, Tijs
Stevenson, Ian
Will, Sebastian
contents Ultracold gases of dipolar molecules have long been envisioned as a platform for the realization of novel quantum phases. Recent advances in collisional shielding, protecting molecules from inelastic losses, have enabled the creation of degenerate Fermi gases and, more recently, Bose-Einstein condensation of dipolar molecules. However, the observation of quantum phases in ultracold molecular gases that are driven by dipole-dipole interactions has so far remained elusive. In this work, we report the formation of self-bound droplets and droplet arrays in an ultracold gas of strongly dipolar sodium-cesium molecules. Starting from a molecular Bose-Einstein condensate (BEC), microwave dressing fields are used to induce dipole-dipole interactions with controllable strength and anisotropy. By varying the speed at which interactions are induced, covering a dynamic range of four orders of magnitude, we prepare droplets under equilibrium and non-equilibrium conditions, observing a transition from robust one-dimensional (1D) arrays to fluctuating two-dimensional (2D) structures. The droplets exhibit densities up to 100 times higher than the initial BEC, reaching the strongly interacting regime, and suggesting the possibility of a quantum-liquid or crystalline state. This work establishes ultracold molecules as a system for the exploration of strongly dipolar quantum matter and opens the door to the realization of self-organized crystal phases and dipolar spin liquids in optical lattices.
format Preprint
id arxiv_https___arxiv_org_abs_2507_15208
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Observation of Self-Bound Droplets of Ultracold Dipolar Molecules
Zhang, Siwei
Yuan, Weijun
Bigagli, Niccolò
Kwak, Haneul
Karman, Tijs
Stevenson, Ian
Will, Sebastian
Quantum Gases
Atomic and Molecular Clusters
Atomic Physics
Quantum Physics
Ultracold gases of dipolar molecules have long been envisioned as a platform for the realization of novel quantum phases. Recent advances in collisional shielding, protecting molecules from inelastic losses, have enabled the creation of degenerate Fermi gases and, more recently, Bose-Einstein condensation of dipolar molecules. However, the observation of quantum phases in ultracold molecular gases that are driven by dipole-dipole interactions has so far remained elusive. In this work, we report the formation of self-bound droplets and droplet arrays in an ultracold gas of strongly dipolar sodium-cesium molecules. Starting from a molecular Bose-Einstein condensate (BEC), microwave dressing fields are used to induce dipole-dipole interactions with controllable strength and anisotropy. By varying the speed at which interactions are induced, covering a dynamic range of four orders of magnitude, we prepare droplets under equilibrium and non-equilibrium conditions, observing a transition from robust one-dimensional (1D) arrays to fluctuating two-dimensional (2D) structures. The droplets exhibit densities up to 100 times higher than the initial BEC, reaching the strongly interacting regime, and suggesting the possibility of a quantum-liquid or crystalline state. This work establishes ultracold molecules as a system for the exploration of strongly dipolar quantum matter and opens the door to the realization of self-organized crystal phases and dipolar spin liquids in optical lattices.
title Observation of Self-Bound Droplets of Ultracold Dipolar Molecules
topic Quantum Gases
Atomic and Molecular Clusters
Atomic Physics
Quantum Physics
url https://arxiv.org/abs/2507.15208