Abstract

Interference between different quantum-mechanical pathways may give rise to suppression or amplification of various optical processes. It can reduce absorption of lower-level atoms in certain frequency ranges without significantly affecting stimulated emission from upper-level atoms. This may result in sign-changing spectral structures in absorption or gain and refractive indexes, dramatic changes in effective nonlinear susceptibilities, decoupling of radiation and matter, and population trapping. In the UV and XVUV ranges, interference at bound-free transitions may be important.

© 1994 Optical Society of America