Optical two-dimensional coherent spectroscopy of cold atoms

We report an experimental demonstration of optical two-dimensional coherent spectroscopy (2DCS) in cold atoms. The experiment integrates a collinear 2DCS setup with a magneto-optical trap (MOT), in which cold rubidium (Rb) atoms are prepared at a temperature of approxi-mately 200 mu K and a number density of 1010 cm-3. With a sequence of femtosecond laser pulses, we first obtain one-dimensional second-and fourth-order nonlinear signals and then acquire both one-quantum and zero-quantum 2D spec-tra of cold Rb atoms. The capability of performing optical 2DCS in cold atoms is an important step toward optical 2DCS study of many-body physics in cold atoms and ulti-mately in atom arrays and trapped ions. Optical 2DCS in cold atoms/molecules can also be a new avenue to probe chemical reaction dynamics in cold molecules.(c) 2022 Optica Publishing Group

Automated summary

We report an experimental demonstration of optical two-dimensional coherent spectroscopy (2DCS) in cold atoms. The experiment successfully obtained two-dimensional spectra of cold rubidium atoms and demonstrated the importance of performing 2DCS in cold atoms.