DFG Logo
Schwerpunktprogramm SPP 1285
Halbleiter Spintronik
Spintronik > Projekte > Projektansicht


Prof. Dr. Christian Schüller

Naturwissenschaftliche Fakultät II - Physik
Universität Regensburg
93040 Regensburg

Dr. Tobias Korn

Naturwissenschaftliche Fakultät II - Physik
Universität Regensburg
93040 Regensburg

Ultrafast and time-resolved Raman spectroscopy of spin excitations in p-doped semiconductor heterostructures

We propose to investigate the spin dynamics of holes and the dynamics of elementary excitations of holes in p-doped GaAs-AlGaAs quantum-well systems. It shall be studied if and how the spin coherence can be controlled either by the manipulation of the band structure via gates or by low Mn or C doping in the quantum wells. In a first part of the project, the spin relaxation and coherence of nonequilibrium holes, as well as anisotropies in the spin relaxation and the g factors, shall be probed by ultrafast interband spectroscopy, like time-resolved Faraday rotation, and by time-resolved photoluminescence. In addition to these well-established techniques, we propose to develop new measurement concepts, namely heterodyne time-resolved Faraday rotation and photoluminescence. These techniques will enable one to extend the temporal window for the measurements up to the range of several hundred nanoseconds, and to probe spin coherences of ground-state carriers at times beyond the photocarrier recombination times. In a second part of the project, the dynamics of charge-neutral spin excitations of two-dimensional hole systems, or of spinflip excitations of carriers bound to Mn impurities, shall be explored using timeresolved Raman scattering.


Wichtige Termine:

15. Sept. 2013:
Deadline für den Sonderband Semiconductor Spintronics (DFG-Abschlussbericht) in physica status solidi b
(nähere Informationen wurden per Email zugeschickt)

30. Sept. - 2. Okt. 2013:
Abschlusstreffen des Schwerpunktprogramms "International workshop on semiconductor spintronics" in der Residenz Würzburg
(nähere Informationen)

Aktuelle Veröffentlichung(en):

C. Drexler, S.A. Tarasenko, P. Olbrich, J. Karch, M. Hirmer, F. Müller, M. Gmitra, J. Fabian, R. Yakimova, S. Lara-Avila, S. Kubatkin, M. Wang, R. Vajtai, P. M. Ajayan, J. Kono, and S.D. Ganichev :  "Magnetic quantum ratchet effect in graphene" Nature Nanotechnology 8, 104 (2013)

J.H. Buß, J. Rudolph, S. Shvarkov, H. Hardtdegen, A.D. Wieck, and D. Hägele:  "Long electron spin coherence in ion‐implanted GaN: The role of localization" Appl. Phys. Lett. 102, 192102 (2013)

D.J. English, J. Hübner, P.S. Eldridge, D. Taylor, M. Henini, R.T. Harley, and M. Oestreich:  "Effect of symmetry reduction on the spin dynamics of (001)-oriented GaAs quantum wells" Phys. Rev. B 87, 075304 (2013)

V.L. Korenev, I.A. Akimov, S.V. Zaitsev, V.F. Sapega, L. Langer, D.R. Yakovlev, Yu. A. Danilov, and M. Bayer:  "Dynamic spin polarization by orientation-dependent separation in a ferromagnet–semiconductor hybrid" Nature Communications 3, 959 (2012)

M. Althammer, E.-M. Karrer-Müller, S.T.B. Goennenwein, M. Opel, R. Gross:  "Spin transport and spin dephasing in zinc oxide" Appl. Phys. Lett. 101, 082404 (2012)