Many-body physics of intersubband polaritons

Intersubband polaritons are light-matter excitations originating from the strong coupling between an intersubband quantum well electronic transition and a microcavity photon mode. Up to now intersubband polaritons have been observed in a wide range of the electromagnetic spectrum from the mid-infrared to the THz regime. Due to their composite bosonic nature, the matter part of these excitations is responsible for a non-trivial dynamics of cavity polaritons. We studied how the Coulomb electron-electron interaction and the Pauli saturation of the electronic transitions affect the many-body physics of intersubband polaritons [1]. As a first application we calculated the efficiency of intersubband polariton-polariton scattering, paving the way to promising quantum non-linear optics especially in the THz regime.\\[4pt] [1] L. Nguyen-Th\^e, S. De Liberato, M. Bamba, C. Ciuti, submitted.