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arXiv · 1304.0037

Dynamic response of a spin-1/2 Kondo singlet

Bryan Hemingway·Stephen Herbert·Michael Melloch·Andrei Kogan
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Abstract

We present a study of spin 1/2 Kondo singlets in single electron transistors under a microwave frequency bias excitation. We compare time-averaged conductance $G$ to predicted universal response with respect to microwave frequency, oscillation amplitude and the Kondo temperature and find a non-adiabatic response when the microwave photon energy $hf$ is comparable to the Kondo temperature $k_B T_K$. We show that our measurements are qualitatively consistent with the predictions for the radiation-induced decoherence rate of the Kondo spin.

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Bryan Hemingway, Stephen Herbert, Michael Melloch, Andrei Kogan. 2013-03-29. Dynamic response of a spin-1/2 Kondo singlet. https://doi.org/10.1103/physrevb.90.125151

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