Observation of bound state self-interaction in a nano-eV atom collider

Published

November 20, 2018

Author(s)

R Thomas, M. Chilcott, A. Deb, Eite Tiesinga, N. Kjaergaard

Abstract

Quantum mechanical scattering resonances for colliding particles occur when a continuum scattering state couples to a discrete bound state between them. The coupling also causes the bound state to interact with itself via the continuum and leads to a shift in the bound state energy, but, lacking knowledge of the bare bound state energy, measuring this self-energy via the resonance position has remained elusive. Here, we report on the direct observation of self-interaction by using a nano- eV atom collider to track the position of a magnetically-tunable Feshbach resonance through a parameter space spanned by energy and magnetic field. Our system of potassium and rubidium atoms displays a strongly non-monotonic res- onance trajectory with an exceptionally large self-interaction energy arising from an interplay between the Feshbach bound state and a different, virtual bound state at a fixed energy below threshold.

Citation

Nature Communications

Volume

9

Pub Type

Journals

Download Paper

https://doi.org/10.1038/s41467-018-07375-8

Local Download

Keywords

laser cooled atom, ultracold collisions, collisional resonances

Citation

Thomas, R. , Chilcott, M. , Deb, A. , Tiesinga, E. and Kjaergaard, N. (2018), Observation of bound state self-interaction in a nano-eV atom collider, Nature Communications, [online], https://doi.org/10.1038/s41467-018-07375-8, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=925544 (Accessed October 27, 2025)