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تسجيل مستخدم جديدDynamics of coupled spins in quantum dots with strong spin-orbit interaction
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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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The spatial separation of electron spins followed by the control of their individual spin dynamics has recently emerged as an essential ingredient in many proposals for spin-based technologies because it would enable both of the two spin species to b
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