Confinement effects in ultrathin ZnO polymorph films: Electronic and optical properties

Lorenzo Sponza, Jacek Goniakowski, and Claudine Noguera
Phys. Rev. B 93, 195435 – Published 25 May 2016
PDFHTMLExport Citation

Abstract

Relying on generalized-gradient and hybrid first-principles simulations, this work provides a complete characterization of the electronic properties of ZnO ultrathin films, cut along the body-centered-tetragonal(010), cubane(100), hexagonal boron nitride(0001), zinc-blende(110), and wurtzite (101¯0) and (0001) orientations. The characteristics of the local densities of states are analyzed in terms of the reduction of the Madelung potential on undercoordinated atoms and surface states/resonances appearing at the top of the valence band and bottom of the conduction band. The gap width in the films is found to be larger than in the corresponding bulks, which is assigned to quantum confinement effects. The components of the high-frequency dielectric constant are determined and the absorption spectra of the films are computed. They display specific features just above the absorption threshold due to transitions from or to the surface resonances. This study provides a first understanding of finite-size effects on the electronic properties of ZnO thin films and a benchmark which is expected to foster experimental characterization of ultrathin films via spectroscopic techniques.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Received 15 March 2016
  • Revised 4 May 2016

DOI:https://doi.org/10.1103/PhysRevB.93.195435

©2016 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Lorenzo Sponza*, Jacek Goniakowski, and Claudine Noguera

  • CNRS, UMR 7588, Institut des Nanosciences de Paris, F-75005 Paris, France
  • and Université Pierre et Marie Curie (Université Paris VI), Paris, France

  • *Present address: King's College of London, London, United Kingdom.
  • Corresponding author: jacek@insp.jussieu.fr

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 93, Iss. 19 — 15 May 2016

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×