Quantitative Model of Heterogeneous Nucleation and Growth of SiGe Quantum Dot Molecules

Hao Hu, Hongjun Gao, and Feng Liu
Phys. Rev. Lett. 109, 106103 – Published 7 September 2012
PDFHTMLExport Citation

Abstract

Using a multiscale approach combining continuum model with first-principles calculation, we develop a quantitative theoretical model for heterogeneous nucleation and the growth of a quantum dot molecule—a few islands “strain bonded” by a pit in heteroepitaxy of thin films, in contrast to homogeneous nucleation and growth of isolated strain islands on the surface. We show that the critical size and energy barrier for island nucleation next to a pit is substantially reduced with the increasing pit size, but the reduction approaches an upper bound of 85% and 72% for the size and barrier, respectively. Our model also predicts a self-limiting effect on island growth, resulting from an intriguing interplay between island-pit attraction and island-island repulsion, that drives the island size to increase linearly with the pit size, which explains a long-standing puzzle of experimental observation.

  • Figure
  • Figure
  • Figure
  • Figure
  • Received 8 May 2012

DOI:https://doi.org/10.1103/PhysRevLett.109.106103

© 2012 American Physical Society

Authors & Affiliations

Hao Hu1,2, Hongjun Gao2, and Feng Liu1,*

  • 1Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA
  • 2Institute of Physics, Chinese Academy of Science, Beijing 100190, China

  • *Corresponding author: fliu@eng.utah.edu

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 109, Iss. 10 — 7 September 2012

Reuse & Permissions
Access Options
CHORUS

Article Available via CHORUS

Download Accepted Manuscript
Collection
Heating up of Superconductors
January 27, 2017

This collection marks the 30th anniversary of the discovery of high-temperature superconductors. The papers selected highlight some of the advances that have been made to date, both in understanding why these compounds behave in the way they do, and in utilizing them in applications. The papers included in the collection have been made free to read.

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Letters

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×