Intersubband polaritonics revisited

We revisit the intersubband polaritonics-the branch of mesoscopic physics, which has a huge potential for optoelectronic applications in the infrared and terahertz domains-and find that, contrary to the general opinion, the Coulomb interactions play a crucial role in the processes of light-matter coupling in the considered systems. Electron-electron and electron-hole interactions radically change the nature of the elementary excitations in these systems. We find that intersubband polaritons represent the result of the coupling of a photonic mode with collective excitations-and not noninteracting electron-hole pairs as it was supposed in the previous works on the subject. (C) 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.JNP.6.061804]