The optical properties and the Franz-Keldysh effect at the direct band gap of GeSn alloys with Sn concentrations up to 4.2% at room temperature were investigated. The GeSn material was embedded in the intrinsic region of a Ge heterojunction photodetector on Si substrates. The layer structure was grown by means of ultra-low temperature molecular beam epitaxy. The absorption coefficient as function of photon energy and the direct bandgap energies were determined. In all investigated samples, the Franz-Keldysh effect can be observed. A maximum absorption ratio of 1.5 was determined for 2% Sn for a voltage swing of 3 V.
%0 Journal Article
%1 oehme2014franzkeldysh
%A Oehme, M
%A Kostecki, K
%A Schmid, M
%A Kaschel, M
%A Gollhofer, M
%A Ye, K
%A Widmann, D
%A Koerner, R
%A Bechler, S
%A Kasper, E
%A Schulze, J
%B Applied Physics Letters
%D 2014
%I American Institute of Physics
%J Appl. Phys. Lett.
%K iht j.schulze.iht journal
%N 16
%P 161115--
%R 10.1063/1.4873935
%T Franz-Keldysh effect in GeSn pin photodetectors
%U https://doi.org/10.1063/1.4873935
%V 104
%X The optical properties and the Franz-Keldysh effect at the direct band gap of GeSn alloys with Sn concentrations up to 4.2% at room temperature were investigated. The GeSn material was embedded in the intrinsic region of a Ge heterojunction photodetector on Si substrates. The layer structure was grown by means of ultra-low temperature molecular beam epitaxy. The absorption coefficient as function of photon energy and the direct bandgap energies were determined. In all investigated samples, the Franz-Keldysh effect can be observed. A maximum absorption ratio of 1.5 was determined for 2% Sn for a voltage swing of 3 V.
@article{oehme2014franzkeldysh,
abstract = {The optical properties and the Franz-Keldysh effect at the direct band gap of GeSn alloys with Sn concentrations up to 4.2% at room temperature were investigated. The GeSn material was embedded in the intrinsic region of a Ge heterojunction photodetector on Si substrates. The layer structure was grown by means of ultra-low temperature molecular beam epitaxy. The absorption coefficient as function of photon energy and the direct bandgap energies were determined. In all investigated samples, the Franz-Keldysh effect can be observed. A maximum absorption ratio of 1.5 was determined for 2% Sn for a voltage swing of 3 V.},
added-at = {2018-11-16T14:18:38.000+0100},
author = {Oehme, M and Kostecki, K and Schmid, M and Kaschel, M and Gollhofer, M and Ye, K and Widmann, D and Koerner, R and Bechler, S and Kasper, E and Schulze, J},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2b72aa1a0ecb3c299af9cf5b72397cfc6/ihtpublikation},
booktitle = {Applied Physics Letters},
comment = {doi: 10.1063/1.4873935},
doi = {10.1063/1.4873935},
interhash = {af9c013ba35bd3026c92896880006985},
intrahash = {b72aa1a0ecb3c299af9cf5b72397cfc6},
issn = {00036951},
journal = {Appl. Phys. Lett.},
keywords = {iht j.schulze.iht journal},
month = apr,
number = 16,
pages = {161115--},
publisher = {American Institute of Physics},
timestamp = {2018-11-16T13:18:38.000+0100},
title = {Franz-Keldysh effect in GeSn pin photodetectors},
url = {https://doi.org/10.1063/1.4873935},
volume = 104,
year = 2014
}