Optical Properties of Self-Assembled Lateral Superlattices in AlInAs Epitaxial Layers and AlAs/InAs Short-Period Superlattices

S. Francoeur, A. G. Norman, M. C. Hanna, A. Mascarenhas, J. L. Reno, D. M. Follstaedt, S. R. Lee

Research output: Contribution to journalArticlepeer-review

4 Scopus Citations

Abstract

Characterization of self-assembled lateral superlattices in AlInAs epitaxial layers and AlAs/InAs short-period superlattices is presented. These structures are spontaneously generated during the epitaxial growth by metal-organic chemical vapor deposition and molecular beam epitaxy. Transmission electron microscopy reveals the structural details and electro-modulated reflectance is used to characterize the energy and anisotropy of the optical transitions in the lateral superlattices. We demonstrate several properties of these self-assembled structures: (a) the band gap energy can be changed by as much as 350 meV, (b) the polarization anisotropy of the lowest energy transition exceeds 90%, (c) the superlattice axis and the direction of the optical anisotropy can be oriented along two non-equivalent directions in the plane of the substrate, and (d) the valence band splitting between heavy- and light-hole transitions is significant. We discuss the difference between the samples from the two growth techniques. Finally, we theoretically model the electronic states in these lateral superlattices and we demonstrate that the difference in average InAs composition between the well and barrier can be as high as 35%.

Original languageAmerican English
Pages (from-to)118-124
Number of pages7
JournalMaterials Science and Engineering: B
Volume88
Issue number2-3
DOIs
StatePublished - 2002

NREL Publication Number

  • NREL/JA-590-32612

Keywords

  • AlAs/InAs short-period layers
  • AlInAs epitaxial layers
  • Optical polarization anisotropy
  • Superlattices

Fingerprint

Dive into the research topics of 'Optical Properties of Self-Assembled Lateral Superlattices in AlInAs Epitaxial Layers and AlAs/InAs Short-Period Superlattices'. Together they form a unique fingerprint.

Cite this