Coupled One- and Two-Photon Resonances in Three Level Atoms

摘要

The coherent excitation of a three level atom by one- and two-photon resonances coupled by a common level is treated by the method of averages. The equations for the density matrix of the three resonant levels are solved analytically for square pulses of duration shorter than relaxation times. Double free induction decay occuring when both exciting fields are switched out of resonance simultaneously is exhibited. The emitted radiation is also calculated for an experiment in which the field driving the one-photon resonance remains on after the other field ends, and it is shown that experiments at several detunings and amplitudes would allow determination of various combinations of relaxation rates. Numerical studies for nonsquare pulses are briefly described. The results show that the main qualitative features of the square-pulse case are retained. 15 references. (ERA citation 04:047616)