Eur. Phys. J. Appl. Phys.
Volume 38, Number 1, April 2007
|Page(s)||21 - 25|
|Section||Nanomaterials and Nanotechnologies|
|Published online||14 February 2007|
Thermally-activated effects on photoluminescence line shape of InAs/GaAs quantum dot heterosystems
Department of Electrical Engineering, Technology and Science Institute of Northern Taiwan, No. 2, Xueyuan Rd., Peitou, 112 Taipei, Taiwan, R.O.C.
2 Department of Electronic Engineering, Chang Gung University, No. 259, Wenhwa 1st Rd., Kweishan, 333 Taoyuan, Taiwan, R.O.C.
Corresponding author: firstname.lastname@example.org
Revised: 7 November 2006
Accepted: 22 December 2006
Published online: 14 February 2007
We investigate the temperature dependence of photoluminescence (PL) properties of InAs/GaAs quantum dot (QD) heterostructures. The temperature dependence of the InAs exciton energy and linewidth is found to display a significant difference due to the different dot size distribution. We propose a model, which takes into account the dot size distribution, state filling effect, carrier thermal escaping and retrapping, and electron-phonon scattering, to explain the carriers transferring mechanisms in the QD system. The experimental results are reproduced well by our model. Sample with lower dot size uniformity reveals evident thermal redistribution effect among dots, but the effect is weak for sample with higher dot size uniformity and is overcome by the electron-phonon scattering, which is consistent with the observed monotonically increasing linewidth of PL spectra with temperature.
PACS: 73.21.La – Quantum dots / 78.55.Cr – III-V semiconductors / 78.67.Hc – Quantum dots
© EDP Sciences, 2007
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.