TY - JOUR T1 - Undressing a collective intersubband excitation in a quantum well JF - Physical Review Letters Y1 - 1996 A1 - Craig, K. A1 - Galdrikian, B. A1 - Heyman, J. N. A1 - Markelz, A. G. A1 - Williams, J. B. A1 - Sherwin, M. S. A1 - Campman, K. A1 - Hopkins, P. F. A1 - Gossard, A. C. AB -

We have experimentally measured the 1-2 intersubband absorption in a single 40 nm wide modulation-doped Al0.3Ga0.7As/GaAs square quantum well as a function of frequency, intensity, and charge density. The low-intensity depolarization-shifted absorption occurs near 80 cm(-1) (10 meV or 2.4 THz), nearly 30% higher than the intersubband spacing. At higher intensities, the absorption peak shifts to lower frequencies. Our data are in good agreement with a theory proposed by Zaluzny, which attributes the redshift to a reduction in the depolarization shift as the excited subband becomes populated.

VL - 76 SN - 0031-9007 N1 - Sherwin, Mark S/Q-4762-2017
Sherwin, Mark S/0000-0002-3869-1893; Markelz, Andrea/0000-0003-0443-4319
78 ER -