Periodically driven two-mode optical systems

Abstract

We consider a two-level atom driven by modulated light and find that complete population inversion can be induced by light without any resonant frequency component. This is in contrast to the familiar case of monochromatic driving in which complete population inversion is only possible with resonant light. This result concerns experimentally realizable systems and hence the effect of spontaneous emission is also considered. We also relate our work to other recent works on quantum double-well. Analogies with the suppression of quantum tunneling and with the low-frequency radiation generation are discussed. By translating the results from the study of the two-level atom to the theory of optical waveguides, we introduce a new geometric representation for analysing the optical state of a single-mode optical coupler. We find that an optical coupler with out-of-phase index modulations can control and suppress the evanescent power transfer between cores. A new type of optical band-pass filter based on the modulated index coupler is proposed. Show more