Observation of Collisions between Two Ultracold Ground-State CaF Molecules

Lawrence W Cheuk; Loïc Anderegg; Yicheng Bao; Sean Burchesky; Scarlett S Yu; Wolfgang Ketterle; Kang-Kuen Ni; John M Doyle

doi:10.1103/PhysRevLett.125.043401

Observation of Collisions between Two Ultracold Ground-State CaF Molecules

Phys Rev Lett. 2020 Jul 24;125(4):043401. doi: 10.1103/PhysRevLett.125.043401.

Authors

Lawrence W Cheuk^{1

2

3}, Loïc Anderegg^{1

2}, Yicheng Bao^{1

2}, Sean Burchesky^{1

2}, Scarlett S Yu^{1

2}, Wolfgang Ketterle^{2

4}, Kang-Kuen Ni^{1

2

5}, John M Doyle^{1

2}

Affiliations

¹ Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
² Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, USA.
³ Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
⁴ Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
⁵ Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.

PMID: 32794819
DOI: 10.1103/PhysRevLett.125.043401

Abstract

We measure inelastic collisions between ultracold CaF molecules by combining two optical tweezers, each containing a single molecule. We observe collisions between ^{2}Σ CaF molecules in the absolute ground state |X,v=0,N=0,F=0⟩, and in excited hyperfine and rotational states. In the absolute ground state, we find a two-body loss rate of 7(4)×10^{-11} cm^{3}/s, which is below, but close to, the predicted universal loss rate.