Abstract

Recently, there has been increasing interest on the idea of controlling optical responses using atomic-coherence or quantum-interferences. Typical example may be the concept of electomagnetically-induced transparency (EIT) [1]. The key idea of EIT is to apply a strong-coupling field between a metastable and upper states to dress them equivalently as two states decaying to a common level or continuum, and to induce the transparency at the split-center of Autler-Townes components. This idea of EIT may open new possibilities to various coherent processes, such as lasing without population inversion, enhanced refractive index without absorption], slow group velocity without absorption, enhanced nonlinearity without absorption, etc.

© 1996 Optical Society of America