TY - JOUR T1 - FAR-INFRARED SATURATION SPECTROSCOPY OF A SINGLE SQUARE-WELL JF - Semiconductor Science and Technology Y1 - 1994 A1 - Craig, K. A1 - Felix, C. L. A1 - Heyman, J. N. A1 - Markelz, A. G. A1 - Sherwin, M. S. A1 - Campman, K. L. A1 - Hopkins, P. F. A1 - Gossard, A. C. AB -
We have performed saturation spectroscopy measurements of the lowest intersubband transition in a single 400 angstrom GaAs/Al0.3Ga0.7As modulation-doped square quantum well. We couple intense tunable far-infrared radiation from the Santa Barbara free electron laser into our sample using an edge-coupling technique and measure absorption as a function of frequency and intensity. Saturation and frequency shifts in the absorption line are clearly observed. We attribute the frequency shifts to reductions in the many-body depolarization shift. From our preliminary measurements, we estimate the intersubband relaxation time to be 600 ps to within a factor of three.
VL - 9 SN - 0268-1242 N1 - Sherwin, Mark S/Q-4762-2017The UCSB free-electron lasers provide kilowatts of continuously tunable radiation from 120 GHz to 4.8 THz. They have the most impact on terahertz science and technology that require a tunable, high power source to explore non-linear dynamics or that sacrifice incident power to recover the linear response of systems with very small cross-section. We describe three experiments that demonstrate the utility of these lasers in experiments on the terahertz dynamics of semiconductor nanostructures: (i) terahertz dynamics of resonant tunneling diodes, (ii) saturation spectroscopy of quantum wells and (iii) photon-assisted tunneling in superlattices.
VL - 60-1 SN - 0022-2313 N1 - Sherwin, Mark S/Q-4762-2017; Guimaraes, Paulo Sergio Soares/B-6918-2012