Spin transport and relaxation

• Applicant: Dr. Tamara Nunner
• Subject Area: Theoretical Condensed Matter Physics
• Term: from 2007 to 2012
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 41017358

Generation of spin currents and transport of spin over relevant distances belong to the major challenges in the field of spintronics. Spin currents can be generated via the spin Hall effect, which is closely related to anomalous Hall effect, or by exploiting spin thermoelectric effects such as the recently observed spin Seebeck effect. We propose to study spin thermoelectric effects in the presence of spin orbit interaction where a nontrivial spin dynamics is expected since spin is not conserved. We plan to extend our theory of the anomalous Hall effect in the presence of magnetic impurities to the diluted magnetic semiconductors, where magnetic impurities are known to play a fundamental role. We also intend to establish a theory for the anomalous Hall effect in strongly disordered systems including quantum corrections and at elevated temperatures including inelastic scattering. Electron-electron interactions can lead to decay of spin currents by transferring momentum between the two spin species. This phenomenon, referred to as spin Coulomb drag, has recently been observed experimentally for the first time. We propose to set up a theory for the spin Coulomb drag in materials with bulk spinorbit interaction, we will investigate spin Coulomb drag in the presence of spin-flip scattering, and we intend to study how spin Coulomb drag affects both the spin Hall and the anomalous Hall effects.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1285: Semiconductor Spintronics
• Participating Person: Professor Dr. Felix von Oppen