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arXiv · 0807.3654

Dynamics of coupled spins in quantum dots with strong spin-orbit interaction

A. Pfund·I. Shorubalko·K. Ensslin·R. Leturcq
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Abstract

We investigated the time dependence of two-electron spin states in a double quantum dot fabricated in an InAs nanowire. In this system, spin-orbit interaction has substantial influence on the spin states of confined electrons. Pumping single electrons through a Pauli spin-blockade configuration allowed to probe the dynamics of the two coupled spins via their influence on the pumped current. We observed spin-relaxation with a magnetic field dependence different from GaAs dots, which can be explained by spin-orbit interaction. Oscillations were detected for times shorter than the relaxation time, which we attribute to coherent evolution of the spin states.

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A. Pfund, I. Shorubalko, K. Ensslin, R. Leturcq. 2008-07-23. Dynamics of coupled spins in quantum dots with strong spin-orbit interaction. https://doi.org/10.1103/physrevb.79.121306

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