Published June 22, 2015 | Version v1
Journal article

Optical properties of individual site-controlled Ge quantum dots

  • 1. Center for Advancing Electronics Dresden, CfAED, TU Dresden (Germany)
  • 2. Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstr. 20, Dresden 01069 (Germany)
  • 3. Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz (Austria)
  • 4. Research Center for Photovoltaics, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)
  • 5. Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)

Description

We report photoluminescence (PL) experiments on individual SiGe quantum dots (QDs) that were epitaxially grown in a site-controlled fashion on pre-patterned Si(001) substrates. We demonstrate that the PL line-widths of single QDs decrease with excitation power to about 16 meV, a value that is much narrower than any of the previously reported PL signals in the SiGe/Si heterosystem. At low temperatures, the PL-intensity becomes limited by a 25 meV high potential-barrier between the QDs and the surrounding Ge wetting layer (WL). This barrier impedes QD filling from the WL which collects and traps most of the optically excited holes in this type-II heterosystem

Additional details

Identifiers

Publishing Information

Journal Title
Applied Physics Letters
Journal Volume
106
Journal Issue
25
Journal Page Range
p. 251904-251904.5
ISSN
0003-6951
CODEN
APPLAB

Optional Information

Notes
(c) 2015 Author(s)