Picosecond and Subpicosecond Luminescence of GaAs/GaAlAs Superlattices
Picosecond and subpicosecond luminescence techniques have been used to study vertical transport in GaAs/GaAlAs superlattices. The great advantages of these techniques are the very good time resolution and the absence of processing of the sample. We describe in this revue the main results and emphasize on some of the interesting aspects of the interpretation of the results. Both electron and hole mobilities can be obtained by using different excitation densities. They are compared with theoretical estimates.
KeywordsHole Mobility Surface Recombination Vertical Transport Excitation Density Capture Time
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- 7.B. Deveaud, J. Shah, T.C. Damen, B. Lambert, A. Chomette, A. Regreny, IEEE J. of Quantum Elec, QE24, (1988)Google Scholar
- 10.L. Reggiani, In “Physics of nonlinear transport In semiconductors”, Ed. D.K. Ferry, J.R. Barker and C. Jacoboni, Plenum press, 243 (1980)Google Scholar
- 15.B. Lambert, B. Deveaud, A. Chomette, A. Regreny, B. Sermage, Proc. Int. Conf. on Superlattices Microstructures and Mlcrodevlces, Trieste 1988 (to be published).Google Scholar
- 20.B. Lambert, B. Deveaud, A. Chomette, A. Regreny, R. Romestain, P. Edel, GaAs and Related Compounds, Inst. Phys. Ser. N°74, 357 (1984)Google Scholar
- 22.Very fast capture in the EW is indeed directly observed in our experiments on GGSLs: no accumulation of carriers in the last SL layer is observed although the excitation density is quite high (see Fig. 3).Google Scholar
- 24.B. Lambert, B. Deveaud, A. Chomette, A. Regreny, B. Sermage, to be publishedGoogle Scholar
- 25.As long as the values of tauw and tausl are reasonable, their influence on the fit is negligeable compared to the influence of Dn which can then be unambiguously determined.Google Scholar
- 29.E. Gobel, R. Hoger and J. Kühl, in Semiconductor quantum well structures and superlattices, p53, (Ed. K. Ploog and N.T. Linh), Les editions de Physique, Les Ulis (1985)Google Scholar
- 32.In the absence of cladding layers, the observed lifetime of the luminescence of a SL is of the order of 500 to 700 ps (D. Block, R. Romestain, B. Lambert, B. Deveaud, A. Regreny, 4th Int. Conf. on Superlattices microstructures and Microdevices, Trieste 1988, to be published). Such a lifetime is easily explained by surface recombination using a diffusion coefficient of 2 to 4 cm2/s, typical for holes at low temperatures.Google Scholar
- 33.We estimate a mean effective temperature for the type of carrier of interest, over the time range of importance: the rise of the EW luminescence. We used an effective temperature of 25K.Google Scholar
- 34.H. Sakaki, M. Tanaka, J. Yoshino, Japan. J. Appl. Phys., 84 (1985)Google Scholar
- 37.C. Guillemot (private comm.)Google Scholar