Chinese Physics Letters

Transparency and Strong Gain Without Population Inversion in Photonic Bandgap Crystals

Chunguang Du, Zhengfeng Hu, Hou Chun-Feng, Shiqun Li

Published Feb 22, 2002• 20 citations

Abstract

Without using the weak-field approximation, we investigate the transient properties of a Λ-type atom with one transition near resonant with a photonic bandgap edge. Whatever the initial state of the atom is, the atom can become transparent to a probe field, and strong gain without population inversion is also possible if the atom has been pre-excited. The defect mode formed by atomic doping can have a strong effect on the absorption properties of the atom.

DOI: 10.1088/0256-307x/19/3/316

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