On the origin of Franz-Keldysh oscillations in AlGaAs/GaAs modulation-doped heterojunctions

R. A. Novellino, C. Vazquez-López, A. A. Bernussi, C. Schmidt, F. Cerdeira, P. Motisuke, F. H. Pollak, F. Meseguer, K. Ploog

Research output: Contribution to journalArticlepeer-review

15 Scopus citations

Abstract

We have performed a series of photoreflectance measurements in a modulation-doped AlGaAs/GaAs heterojunction containing a high mobility two-dimensional electron gas. Measurements were performed as a function of temperature in the range 2 K≤T≤300 K. We studied the Franz-Keldysh oscillations associated with the E0 transition of both the GaAs and AlGaAs. The fields obtained from these oscillations for both sides of the heterojunction are quite different. Also, the temperature dependence of these fields are radically different. In fact, the temperature dependence of the field in the GaAs side of the modulation-doped heterojunction sample is very similar to that of the field in a single undoped GaAs film deposited on a GaAs substrate, where no two-dimensional electron gas is present. This shows that the field producing the observed oscillations on the GaAs side of the modulation-doped heterojunction sample is not related to the field that confines the two-dimensional electron gas.

Original languageEnglish
Pages (from-to)5577-5581
Number of pages5
JournalJournal of Applied Physics
Volume70
Issue number10
DOIs
StatePublished - 1991

Fingerprint Dive into the research topics of 'On the origin of Franz-Keldysh oscillations in AlGaAs/GaAs modulation-doped heterojunctions'. Together they form a unique fingerprint.

Cite this