Observation of spin singlet butterfly Rydberg molecules in an ultracold atomic Rb gas

2025/10/24 by Exner, Markus, Srikumar, Rohan, Blättner, Richard +4
#Atomic Physics (physics.atom-ph) #FOS: Physical sciences

paper · doi:10.48550/arxiv.2510.21620

Abstract

We report the observation of spin-singlet ultra-long range Rydberg butterfly molecules consisting of a ground-state atom bound to a Rydberg atom by P-wave scattering of ⁸⁷Rb Rydberg electrons from ⁸⁷Rb(5s) atoms. A three-photon excitation scheme enables the photoassociation of these molecules by weakly admixing Rb(18f_7/2) states. The measured binding energies, kilo-Debye permanent electric dipole moments, and lifetimes are in excellent agreement with theory. Two long-lived vibrational levels, red detuned from the Rb(18f_7/2) threshold, are observed. This experiment is a foundational step in the production of ultra-cold anions and heavy Rydberg ion-pair systems.

Related

• Novel binding mechanism for ultra-long range molecules
• Laser-assisted binding of ultracold polar molecules with Rydberg atoms in the van der Waals regime
• Exploring the vibrational series of pure trilobite Rydberg molecules
• Probing dipolar interactions between Rydberg atoms and ultracold polar molecules
• Elucidating the roles of collision energy and photon momentum transfer in the formation of ultralong-range Rydberg molecules