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arXiv · 0804.1537

Quenching Spin Decoherence in Diamond through Spin Bath Polarization

Susumu Takahashi·Ronald Hanson·Johan van Tol·Mark S. Sherwin·David D. Awschalom
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Abstract

We experimentally demonstrate that the decoherence of a spin by a spin bath can be completely eliminated by fully polarizing the spin bath. We use electron paramagnetic resonance at 240 gigahertz and 8 Tesla to study the spin coherence time $T_2$ of nitrogen-vacancy centers and nitrogen impurities in diamond from room temperature down to 1.3 K. A sharp increase of $T_2$ is observed below the Zeeman energy (11.5 K). The data are well described by a suppression of the flip-flop induced spin bath fluctuations due to thermal spin polarization. $T_2$ saturates at $\sim 250 μs$ below 2 K, where the spin bath polarization is 99.4 %.

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Susumu Takahashi, Ronald Hanson, Johan van Tol, Mark S. Sherwin, David D. Awschalom. 2008-04-09. Quenching Spin Decoherence in Diamond through Spin Bath Polarization. https://doi.org/10.1103/physrevlett.101.047601

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