Direct laser cooling of a symmetric top molecule
Abstract
Ultracold polyatomic molecules have potentially wide-ranging applications in quantum simulation and computation, particle physics, and quantum chemistry. For atoms and small molecules, direct laser cooling has proven to be a powerful tool for quantum science in the ultracold regime. However, the feasibility of laser-cooling larger, nonlinear polyatomic molecules has remained unknown because of their complex structure. We laser-cooled the symmetric top molecule calcium monomethoxide (CaOCH3), reducing the temperature of ~104 molecules from 22 ± 1 millikelvin to 1.8 ± 0.7 millikelvin in one dimension and state-selectively cooling two nuclear spin isomers. These results demonstrate that the use of proper ro-vibronic transitions enables laser cooling of nonlinear molecules, thereby opening a path to efficient cooling of chiral molecules and, eventually, optical tweezer arrays of complex polyatomic species.
- Publication:
-
Science
- Pub Date:
- September 2020
- DOI:
- 10.1126/science.abc5357
- arXiv:
- arXiv:2004.02848
- Bibcode:
- 2020Sci...369.1366M
- Keywords:
-
- PHYSICS;
- Physics - Atomic Physics;
- Physics - Chemical Physics
- E-Print:
- doi:10.1126/science.abc5357