Phonon modes, dielectric constants, and exciton mass parameters in ternary MgxZn1-xO

Carsten Bundesmann, Michael Lorenz, Marius Grundmann, Mathias Schubert

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Scopus citations

Abstract

The long-wavelength optical phonons and dielectric constants of PLD-grown MgxZn1-xO films are studied by combination of infrared spectroscopic ellipsometry and Raman scattering spectroscopy. The ternary alloy MgxZn1-xO exhibits a phase transition with change of coordination number from four-fold coordinated, hexagonal wurtzite structure (ZnO) to six-fold coordinated, cubic rocksalt structure (MgO). It is found that both phonon mode frequencies and dielectric constants change abruptly upon phase transition, which is assigned to the change of coordination number. The change of dielectric constants can be related to the change of electronic properties, for instance, the exciton binding energy. In a simple approach, the exciton binding energy depends on the reduced exciton mass and the static dielectric constant. By comparison with experimental values of the exciton binding energies it is found that the reduced exciton mass must increase by a factor of about two upon face transition from wurtzite to rocksalt structure.

Original languageEnglish (US)
Title of host publicationCurrent and Future Trends of Functional Oxide Films
Pages13-17
Number of pages5
Publication statusPublished - Dec 1 2006
Event2006 MRS Spring Meeting - San Francisco, CA, United States
Duration: Apr 17 2006Apr 21 2006

Publication series

NameMaterials Research Society Symposium Proceedings
Volume928
ISSN (Print)0272-9172

Other

Other2006 MRS Spring Meeting
CountryUnited States
CitySan Francisco, CA
Period4/17/064/21/06

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ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Bundesmann, C., Lorenz, M., Grundmann, M., & Schubert, M. (2006). Phonon modes, dielectric constants, and exciton mass parameters in ternary MgxZn1-xO. In Current and Future Trends of Functional Oxide Films (pp. 13-17). (Materials Research Society Symposium Proceedings; Vol. 928).