Optical switching of one-dimensional photonic band gaps and coherent generation of dark and bright optical lattices in quantum wells

We propose one-dimensional bright and dark optical lattices where Bragg scattering occurs, respectively, via periodic generation of gain without inversion and electromagnetically induced absorption in the absence of any refractive index perturbation. The absorption and gain processes are caused by quantum interference in the conduction intersubband transitions of a corrugated n-doped quantum well structure interacting with an intense infrared laser. The quantum well structure is embedded between two optical confinement layers, forming a periodic structure with a Bragg wavelength similar to that of the intersubband transition between the second and third conduction subbands of the quantum well. We show that in the absence of the intense infrared laser this transition is transparent, and the periodic structure forms a passive one-dimensional photonic gap generated by the background refractive index contrast of the corrugated region. In the presence of this laser, the intersubband transition is influenced by the quantum coherence effects, causing dramatic changes in the photonic band gap. We show that when one adjusts the intensity and wavelength of such a laser properly these effects can (i) destroy the one-dimensional photonic band gap, and (ii) form periodic regions of gain without inversion or electromagnetically induced loss, while the index perturbation is completely canceled out. Such bright and dark optical lattices can scatter a light at Bragg wavelength when its frequency is the same or close to that of the intersubband transition.