Stability of adiabatic states in a dissipative three-level system

The necessary and sufficient conditions for the stability of adiabatic states in three-level quantum systems are investigated analytically and numerically. Various possible configurations of three-level systems under exact two-photon resonance are considered. It is shown that in all these schemes, the lifetime of the studied states is determined by the dephasing time between levels that are not connected by a dipole transition. An efficient population transfer through the b-state at room temperature is demonstrated despite relatively long relaxation times. It is also demonstrated that, in case of large one-photon detuning, the so-called b-state has the same lifetime as that of the dark state. The evolution of adiabatic states for arbitrary values of single-photon detunings has been studied numerically.