Excitons in germanium nanowires: Quantum confinement, orientation, and anisotropy effects within a first-principles approach

被引:93
作者
Bruno, M
Palummo, M
Marini, A
Del Sole, R
Olevano, V
Kholod, AN
Ossicini, S
机构
[1] Univ Roma Tor Vergata, ETSF, I-00133 Rome, Italy
[2] Univ Roma Tor Vergata, Dipartimento Fis, INFM, CNR, I-00133 Rome, Italy
[3] CNRS, ETSF, F-38042 Grenoble, France
[4] CNRS, LEPES, F-38042 Grenoble, France
[5] Fed Off Commun, CH-2501 Biel, Switzerland
[6] Univ Modena & Reggio Emilia, Dipartimento Sci & Metodi Ingn, I-42100 Reggio Emilia, Italy
[7] Univ Modena & Reggio Emilia, INFM, Natl Ctr Nanostruct & Biosyst Surfaces S3, I-42100 Reggio Emilia, Italy
来源
PHYSICAL REVIEW B | 2005年 / 72卷 / 15期
关键词
D O I
10.1103/PhysRevB.72.153310
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Within a first-principles framework we show how many-body effects crucially modify the electronic and optical properties of free-standing Germanium nanowires. The electron-hole binding energy and probability distribution are found to depend on both wire size and orientation. Moreover, we observe an almost complete compensation of self-energy and excitonic effects for some of the analyzed quantum wires, which we explain as being due to their clusterlike atomic structure.
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页数:4
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