@article {265, title = {Undressing a collective intersubband excitation in a quantum well}, journal = {Physical Review Letters}, volume = {76}, number = {13}, year = {1996}, note = {Sherwin, Mark S/Q-4762-2017
Sherwin, Mark S/0000-0002-3869-1893; Markelz, Andrea/0000-0003-0443-4319
78}, month = {Mar 25}, pages = {2382-2385}, abstract = {

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.

}, isbn = {0031-9007}, doi = {10.1103/PhysRevLett.76.2382}, author = {Craig, K. and Galdrikian, B. and Heyman, J. N. and Markelz, A. G. and Williams, J. B. and Sherwin, M. S. and Campman, K. and Hopkins, P. F. and Gossard, A. C.} } @article {272, title = {NONLINEAR QUANTUM DYNAMICS IN SEMICONDUCTOR QUANTUM-WELLS}, journal = {Physica D-Nonlinear Phenomena}, volume = {83}, number = {1-3}, year = {1995}, note = {Sherwin, Mark S/Q-4762-2017
Sherwin, Mark S/0000-0002-3869-1893; Markelz, Andrea/0000-0003-0443-4319
14th Annual International Conference of the Center-for-Nonlinear-Studies - Quantum Complexity in Mesoscopic Systems
May 16-20, 1994
Los alamos, nm
Ctr nonlinear studies
34}, month = {May 15}, pages = {229-242}, abstract = {

We discuss recent measurements of the nonlinear response of electrons in wide quantum wells driven by intense electromagnetic radiation at terahertz frequencies. The theme is the interplay of quantum mechanics, strong periodic driving, the electron-electron interaction and dissipation. We discuss harmonic generation from an asymmetric double quantum well in which the effects of dynamic screening are important. Measurements and theory are found to be in good agreement. We also discuss intensity-dependent absorption in a 400 Angstrom square quantum well. A new nonlinear quantum effect occurs, in which the frequency at which electromagnetic radiation is absorbed shifts to the red with increasing intensity. The preliminary experimental results are in agreement with a theory by Zaluzny, in which the source of the nonlinearity is the self-consistent potential in the Hartree approximation for the electron dynamics.

}, isbn = {0167-2789}, doi = {10.1016/0167-2789(94)00266-S}, author = {Sherwin, M. S. and Craig, K. and Galdrikian, B. and Heyman, J. and Markelz, A. and Campman, K. and Fafard, S. and Hopkins, P. F. and Gossard, A.} } @proceedings {320, title = {Far-infrared nonlinear response of electrons in semiconductor nanostructures}, volume = {1854}, year = {1993}, pages = {36-47}, author = {Sherwin, M. S. and Asmar, N. G. and Bewley, W. W. and Craig, K. and Felix, C. L. and Galdrikian, B. and Gwinn, E. G. and Markelz, A.G. and Gossard, A. C. and Hopkins, P. F. and Sundaram, M. and Birnir, B.} }