Dresden 2006 – wissenschaftliches Programm
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TT: Tiefe Temperaturen
TT 21: Transport: Nanoelectronics II - Spintronics and Magnetotransport - Part 2
TT 21.7: Vortrag
Dienstag, 28. März 2006, 18:00–18:15, HSZ 105
Effects of Disorder and Reduced Adiabaticity on the Topological Hall Effect — •Michael Wimmer, Tobias Breu, and Klaus Richter — Institut für Theoretische Physik, Universität Regensburg
In the Topological Hall Effect (THE), a non-vanishing Hall effect is introduced not by a magnetic field, but by the Berry phase of spins adiabatically following a magnetic texture. Based on theoretical considerations on a clean, perfectly adiabatic system, an experimental realization was proposed in [1]. However, a real system might not be perfectly adiabatic: For example, elastic scattering has shown to be impairing adiabaticity [2].
We have developed a recursive Green’s function algorithm to calculate the conductance of a four-terminal structure and present numerical studies on the THE. Our main focus is on the effects of disorder and on parameters outside the perfectly adiabatic regime. First results indicate that the THE persists for scattering lengths in reach of experiment.
[1] P. Bruno, V. K. Dugaev, and M. Taillefumier, Phys. Rev. Lett 93, 096806 (2004)
[2] M. Popp, D. Frustaglia, K. Richter, Phys. Rev. B 68, 041303 (2003).