Coherent control of quantum states by quadratically chirped short laser pulses

We present a scheme for coherent manipulation of populations and robust creation of arbitrary coherent superposition of metastable states of a quantum system with lambda configuration of operating energy levels using laser pulses with a quadratically chirped carrier frequency. The case of a single “broadband” laser pulse is considered, when the width of the laser pulse frequency spectrum (without chirp) exceeds the frequency distance between the metastable energy levels of the system. The results of the dressed state analysis and numerical simulation are presented, demonstrating reliable, robust, and rapid creation of an arbitrary coherent superposition of metastable states by changing the parameters of the laser pulses.