Experimental evidence of delocalized states in random dimer superlattices

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Bellani, V.
Díez, E.
Hey, R.
Toni, L.
Tarricone, L.
Parravicini, G.B.
Gómez-Alcalá, R.
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American Physical Society
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We study the electronic properties of GaAs-AlGaAs superlattices with intentional correlated disorder by means of photoluminescence and vertical de resistance. The results are compared to those obtained in ordered and uncorrelated disordered superlattices. We report the first experimental evidence that spatial correlations inhibit localization of states in disordered low-dimensional systems, as our previous theoretical calculations suggested, in contrast to the earlier belief that all eigenstates are localized.
© 1999 The American Physical Society. Work in Italy has been supported by the INFM Network “Fisica e Tecnologia dei Semiconduttori III-V” and in Madrid by the CAM under Project No. 07N/0034/1998. E. D. and F. D.-A. thank A. Sánchez for collaboration on these topics during these years.
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