Dresden 2014 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 78: Quantum dots: Preparation and characterization
HL 78.5: Talk
Wednesday, April 2, 2014, 17:30–17:45, POT 251
GaAs quantum dots in shallow and deep nanoholes fabricated by local droplet etching — •Christian Heyn, Achim Küster, David Sonnenberg, Andreas Graf, Arne Ungeheuer, and Wolfgang Hansen — Institute of Applied Physics, University of Hamburg, D-20355 Hamburg, Germany
We fabricate GaAs quantum dots (QDs) by filling of nanoholes drilled in an AlGaAs substrate utilizing local droplet etching (LDE) [1]. The etching process takes place in a self-assembled fashion during molecular beam epitaxy (MBE) without the need of additional equipment. Using Al droplets as etchant, the nanohole depth d can be varied from less than 10 to more than 100 nm in a controlled fashion. Optical studies of single LDE GaAs QDs show clear excitonic features [2]. Here, we compare the single-dot photoluminescence emission of low-density (N ≃ 107 cm−2) QDs formed by partial filling of either shallow (d ≃ 10 nm) or deep (d = 70 - 100 nm) holes.
[1] Ch. Heyn, A. Stemmann, T. Köppen, Ch. Strelow, T. Kipp, S. Mendach, and W. Hansen, Appl. Phys. Lett. 94, 183113 (2009).
[2] Ch. Heyn, Ch. Strelow, and W. Hansen, New Journal of Physics 14, 053004 (2012).