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arXiv · 1208.5473

Probing dynamics of an electron-spin ensemble via a superconducting resonator

V. Ranjan·G. de Lange·R. Schutjens·T. Debelhoir·J. P. Groen·D. Szombati·D. J. Thoen·T. M. Klapwijk·R. Hanson·L. DiCarlo
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Abstract

We study spin relaxation and diffusion in an electron-spin ensemble of nitrogen impurities in diamond at low temperature (0.25-1.2 K) and polarizing magnetic field (80-300 mT). Measurements exploit mode- and temperature-dependent coupling of hyperfine-split sub-ensembles to the resonator. Temperature-independent spin linewidth and relaxation time suggest that spin diffusion limits spin relaxation. Depolarization of one sub-ensemble by resonant pumping of another indicates fast cross-relaxation compared to spin diffusion, with implications on use of sub-ensembles as independent quantum memories.

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V. Ranjan, G. de Lange, R. Schutjens, T. Debelhoir, J. P. Groen, D. Szombati, D. J. Thoen, T. M. Klapwijk, R. Hanson, L. DiCarlo. 2012-08-27. Probing dynamics of an electron-spin ensemble via a superconducting resonator. https://doi.org/10.1103/physrevlett.110.067004

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