Coherent control of spontaneous emission of a three-level atom in a   coherent photonic band gap reservoir
  By studying the fluorescence and optical properties of a three-level system, we propose a new point of view on the coherent control of these spectra. With the definite phase difference between the fields of the air band and dielectric band in photonic band gap (PBG) reservoirs, the spectra of spontaneous emission, absorption, and dispersion exhibit the coherent property and quantum interference effect. This coherent interference depending on the position of the embedded atom and the width of band gap causes the coupling of the free-space light and the PBG light to result in blue shift of spectra and the appearance of dark lines and kinks. By coherently controlling the position-dependent dispersion, we can tune the frequency of slow light. 
Szu-Cheng Cheng, Jing-Nuo Wu, Tzong-Jer Yang, Wen-Feng Hsieh