Details

Autor(en) / Beteiligte

• Campbell, W.C.
• Augenbraun, B.L.

Titel

Photon spin molasses for laser cooling molecular rotation

Ist Teil von

• Journal of molecular spectroscopy, 2022-03, Vol.385, p.111596, Article 111596

Ort / Verlag

Elsevier Inc

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Laser cooling of translational motion of small molecules is performed by addressing transitions that ensure spontaneous emission cannot cause net rotational excitation. This will not be possible once the rotational splitting becomes comparable to the operational excitation linewidth, as will occur for large molecules or wide bandwidth lasers. We show theoretically that in this regime, angular momentum transfer from red-detuned Doppler cooling light can also exert a damping torque on linear molecules, cooling rotation to the same Doppler limit (typically ≈500 μK for molecules with ≈10ns excited-state lifetimes). This cooling process is derived from photon spin, and indicates that standard optical molasses can also cool molecular rotation with no additional experimental resources. [Display omitted] •Doppler laser cooling is shown to cool molecular rotation with no additional resources.•Large molecules may be amenable to rotational cooling to sub-millikelvin temperatures.•Laser cooling of molecular rotation with broadband pulses extends this to smaller molecules.