TITLE

Room-temperature exciton transitions in partially intermixed GaAs/AlGaAs superlattices

AUTHOR(S)
Ralston, J. D.; O’Brien, S.; Wicks, G. W.; Eastman, L. F.
PUB. DATE
May 1988
SOURCE
Applied Physics Letters;5/2/1988, Vol. 52 Issue 18, p1511
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Substantial increases are observed in the energies of room-temperature exciton transitions in GaAs/AlGaAs superlattices which have been partially intermixed via the impurity-free vacancy diffusion process. Localized intermixing of the layered structure was accomplished by selective deposition of a SiO2 capping layer followed by rapid thermal annealing at temperatures between 850 and 950 °C for 15 s. In the samples studied, the above process allows continuously variable energy shifts of at least 61 meV while still maintaining clearly resolved excitonic behavior. Shifting and broadening of the exciton transitions are studied using room-temperature photoluminescence and photocurrent spectroscopies. A transmission resonance calculation is used to determine the interdiffusion coefficient as a function of temperature from the measured energy shifts.
ACCESSION #
9826677

 

Related Articles

  • Effect of the coherence of free electron–hole pairs on excitonic absorption in GaAs/AlGaAs superlattices. Litvinenko, K. L.; Lysenko, V. G.; Hvam, J. M. // JETP Letters;1/10/98, Vol. 67 Issue 1, p67 

    The effect of photoexcited free carriers on the absorption spectra dynamics of GaAs/Al[sub x]Ga[sub 1-x]As superlattices is investigated experimentally by the pump–probe method. A sharp change in the shift of the excitonic resonance energy from the low- to the high-energy direction is...

  • Photoluminescence decay time studies of type-II GaAs/AlAs quantum well structures. Sturge, M. D.; Mackay, Janet L.; Maloney, Colette; Pribram, J.K. // Journal of Applied Physics;12/1/1989, Vol. 66 Issue 11, p5639 

    Argues that the nonexponential decay of X-point excitons in type-II gallium arsenide (GaAs)/AlAs superlattices is due to spectral diffusion within the inhomogeneous line. Equation for the intensity after a δ-function exciting pulse; Plot of the time decay of the X-exciton emission in the...

  • Linear coefficients of photoelasticity in multilayer quantum well structures having a sloping bottom in exciton resonance regions. Ayukhanov, R. A.; Shkerdin, G. N. // Physics of the Solid State;Sep98, Vol. 40 Issue 9, p1582 

    An analytic expression is obtained for the linear coefficients of photoelasticity in multilayer quantum-well structures having a sloping bottom in the region of the fundamental exciton resonance. The coefficients of photoelasticity are calculated for a GaAs/Al[sub 0.28]Ga[sub 0.72]As...

  • Exchange interactions of excitons localized at opposite interfaces in type-II GaAs/AlAs superlattices: Optically detected magnetic resonance and level anticrossing. Baranov, P. G.; Romanov, N. G.; Hofstaetter, A.; Scharmann, A.; Schnorr, C.; Ahlers, F. J.; Pierz, K. // JETP Letters;11/25/96, Vol. 64 Issue 10, p754 

    Two types of excitons, localized at opposite interfaces and characterized by different magnitudes of the exchange interactions at the same radiation energies, are simultaneously in type-II GaAs/AlAs superlattices. It is shown that the additional long-wavelength luminescence line in superlattices...

  • Exciton spectra of semiconductor superlattices in a parallel magnetic field. Sibel’din, N. N.; Skorikov, M. L.; Tsvetkov, V. A. // Physics of the Solid State;May98, Vol. 40 Issue 5, p764 

    Low-temperature photoluminescence and photoluminescence excitation spectra of GaAs/AlGaAs semiconductor superlattices having different potential barrier widths (b = 20, 30, 50, and 200 Ã…), i.e., degrees of tunnel coupling between quantum wells, are studied in magnetic fields up to 5 T...

  • Raman spectroscopy of resonance exciton tunneling in GaAs/AlAs superlattices in electric fields. Sapega, V. F.; Ruf, T.; Cardona, M.; Grahn, H. T.; Ploog, K. // Physics of the Solid State;May98, Vol. 40 Issue 5, p761 

    Optical-resonance-Raman scattering by acoustic phonons is used to study the effect of an electric field on the state of excitons in GaAs/AlAs superlattices. When the energy of the exciting photon coincides with the energy of an exciton bound to Wannier-Stark states of a heavy hole and electron...

  • Exciton–exciton collisions and conversion of interwell excitons in GaAs/AlGaAs superlattices. Filin, A. I.; Timofeev, V. B.; Gubarev, S. I.; Birkedal, D.; Hvam, J. M. // JETP Letters;4/25/97, Vol. 65 Issue 8, p656 

    The ratio of the densities of intra- and interwell excitons in a symmetric system of coupled quantum wells — a superlattice based on a GaAs/AlGaAs heterostructure — is investigated over a wide range of optical excitation power densities. Conversion of interwell excitons into...

  • Quantum Interference and Localization in Disordered GaAs/AlGaAs Superlattices. Pusep, Yu. A. // AIP Conference Proceedings;2005, Vol. 772 Issue 1, p1007 

    The coherence and the dimensionality of electrons were studied in the intentionally disordered GaAs/AlGaAs superlattices where the disorder was produced either by the random variation of the well thicknesses or by the interface roughness. Depending on relative values of the disorder energy and...

  • Coherent Electron–Hole BCS State: Study of Dynamics. Vasil’ev, P. P.; Kan, H.; Ohta, H.; Hiruma, T. // Journal of Experimental & Theoretical Physics;Feb2003, Vol. 96 Issue 2, p310 

    The first experimental study of the evolution of a coherent electron-hole (e-h) BCS-like state in bulk GaAs at room temperature is presented. We explicitly demonstrate that the total spontaneous emission from e-h pairs located within the conduction and valence bands approaches zero when the...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics