01316nas a2200229 4500008004100000020001400041245006500055210006300120260000800183300001200191490000600203520067700209100001400886700001800900700001900918700002000937700002000957700002000977700002000997700002001017856004901037 1994 eng d a0268-124200aFAR-INFRARED SATURATION SPECTROSCOPY OF A SINGLE SQUARE-WELL0 aFARINFRARED SATURATION SPECTROSCOPY OF A SINGLE SQUAREWELL cMay a627-6290 v93 a
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.
1 aCraig, K.1 aFelix, C., L.1 aHeyman, J., N.1 aMarkelz, A., G.1 aSherwin, M., S.1 aCampman, K., L.1 aHopkins, P., F.1 aGossard, A., C. uhttps://markelz.physics.buffalo.edu/node/26401594nas a2200337 4500008004100000020001400041245009400055210006900149260000800218300001200226490000900238520066100247100001800908700001400926700001800940700001800958700001900976700002100995700001701016700002001033700001501053700001801068700002001086700002001106700002001126700002001146700001301166700001201179700001601191856004901207 1994 eng d a0022-231300aPROBING TERAHERTZ DYNAMICS IN SEMICONDUCTOR NANOSTRUCTURES WITH UCSB FREE-ELECTRON LASERS0 aPROBING TERAHERTZ DYNAMICS IN SEMICONDUCTOR NANOSTRUCTURES WITH cApr a250-2550 v60-13 aThe 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.
1 aAllen, S., J.1 aCraig, K.1 aFelix, C., L.1 aGuimaraes, P.1 aHeyman, J., N.1 aKaminski, J., P.1 aKeay, B., J.1 aMarkelz, A., G.1 aRamian, G.1 aScott, J., S.1 aSherwin, M., S.1 aCampman, K., L.1 aHopkins, P., F.1 aGossard, A., C.1 aChow, D.1 aLui, M.1 aLiu, T., Y. uhttps://markelz.physics.buffalo.edu/node/25700717nas a2200241 4500008004100000245008100041210006900122300001000191490000900201100002000210700001800230700001900248700001400267700001800281700001900299700001800318700001800336700002000354700002000374700001700394700001500411856004900426 1993 eng d00aFar-infrared nonlinear response of electrons in semiconductor nanostructures0 aFarinfrared nonlinear response of electrons in semiconductor nan a36-470 v18541 aSherwin, M., S.1 aAsmar, N., G.1 aBewley, W., W.1 aCraig, K.1 aFelix, C., L.1 aGaldrikian, B.1 aGwinn, E., G.1 aMarkelz, A.G.1 aGossard, A., C.1 aHopkins, P., F.1 aSundaram, M.1 aBirnir, B. uhttps://markelz.physics.buffalo.edu/node/320