Ultrafast nonlinear optical response of photoexcited Ge/SiGe quantum wells: Evidence for a femtosecond transient population inversion

被引：72

作者：

Lange, C. ^{[1
,2
]}

Koester, N. S. ^{[1
,2
]}

Chatterjee, S. ^{[1
,2
]}

Sigg, H. ^{[3
]}

Chrastina, D. ^{[4
,5
]}

Isella, G. ^{[4
,5
]}

von Kaenel, H. ^{[4
,5
]}

Schaefer, M. ^{[6
]}

Kira, M. ^{[6
]}

Koch, S. W. ^{[6
]}

机构：

[1] Univ Marburg, Fac Phys, D-35032 Marburg, Germany

[2] Univ Marburg, Ctr Mat Sci, D-35032 Marburg, Germany

[3] Paul Scherrer Inst, Lab Micro & Nanotechnol, CH-5232 Villigen, Switzerland

[4] CNISM, Dipartimento Fis, Politecn Milan, I-22100 Como, Italy

[5] Polo Como, L NESS, I-22100 Como, Italy

[6] Univ Marburg, Dept Phys & Mat Sci, D-35032 Marburg, Germany

来源：

PHYSICAL REVIEW B | 2009年 / 79卷 / 20期

关键词：

carrier relaxation time; charge injection; elemental semiconductors; germanium; high-speed optical techniques; many-body problems; nonlinear optics; photoexcitation; semiconductor quantum wells; silicon; silicon compounds; time resolved spectra; FREE-CARRIER ABSORPTION; SCATTERING; GAAS; GE;

D O I：

10.1103/PhysRevB.79.201306

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Femtosecond time-resolved pump-probe spectroscopy is used to investigate the ultrafast carrier dynamics of Ge/SiGe quantum wells grown on a Si substrate. Pronounced nonequilibrium effects in the relaxation dynamics of the optically injected carrier distributions are observed and analyzed using a microscopic many-body theory. Transient population inversion and optical gain is obtained on a femtosecond time scale for excitation at energies slightly above the lowest direct quantum-well transition.

引用

页数：4

共 20 条

[1] Optical transitions in Ge/SiGe multiple quantum wells with Ge-rich barriers [J].