In the planned priority program, the physical basics for future semiconductor electronics using the degree of freedom 'spin' are to investigated by intensive cooperation of theoretical, experimental and material oriented groups. The priority program conduces to the coordinated consolidation of multiple, so far divided scientific disciplines. In the first phase of the priority program, the focus is on the combination of theory, experimental physics and materials science. In the second half, besides the basic principles the scientific engineering - represented in the first half by for instance Prof. Osten - component will be strengthened to attach more importance to the evaluation of novel devices and quantum-mechanical circuits. The scientific goals and the work program are separated into the same range of topics for having a better structure. With regards to content the listed scientific goals of course are definitely mixed.
The injection of spin polarized electrons or the local polarization is a basic requirement for a future spintronic. The goal in line with the priority programs is an efficient, electrical spin alignment in semiconductors at room temperature.
The spin-orbit coupling will be used in spintronics for aimed manipulation of spins. Simultaneously the spin-orbit interaction is responsible for the loss of spin orientation during the transport. The goal is a better understanding of the spin relaxation for being able to control the spin relaxation times. For this, priority is given to the extremely long spin relaxation times to avoid loss of the spin orientation during the transport. On the other hand, ultra short spin relaxation times become interesting in very fast devices will be investigated.
Spin dynamics / aimed manipulation of the spin
For many logical and optical spin devices the aimed manipulation of spin is a basic requirement. Therefore, the goal is to control the spin orientation by electrical or optical signals reproducible.
The most spintronic devices will not work with single spins. Therefore, the spin-spin interaction plays an important role. A detailed understanding of electron-nucleus interaction is important because the hyperfine interaction may have a considerable influence on the electron spin dynamic and relaxation. The understanding of interaction between electron spins is basic to be able to use the alignment of the electron spins in semiconductors close to magnetic domains (Proximity effect) and to understand the group velocity in spin systems.
Spin-electronic and spin-optoelectronic devices
Currently, most activities worldwide concentrate on the physical basics of spintronics. Goal of this priority program is the evaluation of novel concepts for spintronic devices. In particular, also complex logical devices should be evaluated where for instance the spin information in the whole circuit stays conserved and the spin-charge transformation is displaced outside.
Spin quantum information processing
The spin quantum computer would be the ultimate spintronic device. Goal of this priority program is to create an interface to the current quantum computer science, to develop concepts for spin quantum gates based on semiconductors and to devolve existing concepts of quantum information processing to simple, quantum mechanical spintronic devices.
30. Sept. - 2. Oct. 2013:
final meeting of priority program "International workshop on semiconductor spintronics" located in the Residenz Würzburg
(further information will follow)
15. Aug. 2013:
Deadline for the special volume semiconductor spintronics (DFG final report) in physica status solidi b
(further information will follow)
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)
H. Horn, A. Balocchi, X. Marie, A. Bakin, A. Waag, M. Oestreich, and J. Hübner: "Spin noise spectroscopy of donor-bound electrons in ZnO" Phys. Rev. B 87, 045312 (2013)
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)
P.S. Eldridge, J. Hübner, S. Oertel, R.T. Harley, M. Henini, and M. Oestreich: "Spin-orbit fields in asymmetric (001)-oriented GaAs/AlxGa1-xAs quantum wells" Physical Review B (Rapid Comm.) 83, 041301(R) (2011)
J. Karch et al.: "Dynamic Hall Effect Driven by Circularly Polarized Light in a Graphene Layer" Phys. Rev. Lett. 105, 227402 (2010)