Two-Electron Linear Intersubband Light Absorption in a Biased Quantum Well

J. Dai, M. E. Raikh, T. V. Shahbazyan
2006 Physical Review Letters  
We point out a novel manifestation of many-body correlations in the linear optical response of electrons confined in a quantum well. Namely, we demonstrate that along with conventional absorption peak at frequency close to intersubband energy, there exists an additional peak at double frequency. This new peak is solely due to electron-electron interactions, and can be understood as excitation of two electrons by a single photon. The actual peak lineshape is comprised of a sharp feature, due to
more » ... xcitation of pairs of intersubband plasmons, on top of a broader band due to absorption by two single-particle excitations. The two-plasmon contribution allows to infer intersubband plasmon dispersion from linear absorption experiments.
doi:10.1103/physrevlett.96.066803 pmid:16606029 fatcat:7wpyowvx3jh4jcdhxwbj5dz3vq