Intersubband polaritons are robust against inhomogeneous broadening induced by multiple quantum wells
Authors: Manceau J-M., Biasiol G., Tran N.L., Carusotto I., Colombelli R.
Autors Affiliation: Univ Paris 11, CNRS UMR9001, C2N, F-91405 Orsay, France; CNR IOM, Lab TASC, Area Sci Pk,SS 14 Km 163-5 Basovizza, I-34149 Trieste, Italy; INO CNR BEC Ctr, I-38123 Povo, Italy and Univ Trento, Dipartimento Fis, I-38123 Povo, Italy.
Abstract: We show that intersubband (ISB) polaritons are robust to inhomogeneous broadening. In a series of multiple quantum well samples with mid-infrared ISB absorption transitions with broadenings varying by a factor of 5 (from 4 meV to 20 meV), we observed polariton linewidths lying in the 4 – 7 meV range only. We have verified the dominantly inhomogeneous origin of the broadening of the ISB transition, and that the linewidth reduction of the modes persists up to room-temperature. The immunity to inhomogeneous broadening is a direct consequence of the coupling of the large number of ISB oscillators to a single photonic mode.
KeyWords: mid-infrared; intersubband polaritons; Connecting to view paper tab on IsiWeb: Click here