Laser Cooling of Complex Molecules for Quantum Science
Abstract
The polyatomic molecule calcium monomethoxide (CaOCH3) will be laser cooled into the ultracold regime (below 1 mK). This will be the first endeavor to apply traditional style laser cooling schemes to a symmetric top molecule. To reach microkelvin (?K) temperatures, many photon scattering events are needed, a challenge for molecules, which lack simple cycling transitions. However, by pre cooling to ~1 K with a cryogenic buffer gas beam, the number of required photon scattering events is reduced, and multiple lasers can be applied to optically cycle CaOCH3 thousands of times. This is sufficient to slow and cool the cryogenic beam to near zero velocities in order to confine them inside a magneto optical trap (MOT). Furthermore, grey and lambda enhanced molasses can be used to achieve temperatures in the ~10 ?K range. Once the molecules are in the ultracold regime, collisional cooling inside an optical trap can be used to increase phase space density and approach the quantum degenerate regime. Optical trapping was recently accomplished for laser cooled CaF in our group and we aim to achieve the same conditions for CaOCH3. The cooling methods to be demonstrated with CaOCH3 are envisioned to be applicable to other, still more complicated molecules such as asymmetric rotor and chiral variants, CaOCH2(CH3) and CaOCHD(CH3). Molecules in the ultracold regime are controllable at the single quantum state level, allowing for novel, systematic study of stereodynamics and mode selective chemistry in the quantum regime.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 14, 2022
- Source ID
- FA95501910068
Entities
People
- John M. Doyle
Organizations
- Air Force Office of Scientific Research
- President and Fellows of Harvard College
- United States Air Force