Adiabatic Passage Control Methods in Ultracold Alkali Atoms and Molecules with Chirped Laser Pulses and Optical Frequency Comb

The adiabatic passage based control methods have been developed to advance a cutting-edge research area of ultracold physics. We studied the controlled excitation of Rydberg atoms, population inversion within hyperfine states of alkali atoms and control of internal degrees of freedom in diatomic polar molecules. We have developed an optical frequency comb based method for creation of ultracold molecules. These works are on demand due to an urgent need in the novel methods for the ultracold molecules production and ultracold quantum control. We make use of chirped pulses and optical frequency combs with the modulation in the form of the sinusoid function. This allowed us to achieve the adiabatic regime of excitations, robust in experimental realization. Particularly, the idea of the implementation of optical frequency combs is in creation of a quasi-dark state, which minimizes population of the transitional, vibrational state manifold, and efficiently mitigates decoherence in the system. We studied the parity of the chirp and showed that it is an important factor in achieving a predetermined quantum yield. We also utilized the adiabatic passage for remote molecular detection by using coherent anti-Stokes Raman spectroscopy (CARS). We developed a semiclassical theory of light propagation through the dispersive medium and estimated the number of photons detectable in the CARS backward signal. The results of investigations significantly advance the frontiers of quantum control at room and ultracold temperature.