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arXiv · 1612.04783

Measurement of the excited-state transverse hyperfine coupling in NV centers via dynamic nuclear polarization

F. Poggiali·P. Cappellaro·N. Fabbri
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Abstract

Precise knowledge of a quantum system's Hamiltonian is a critical pre-requisite for its use in many quantum information technologies. Here, we report a method for the precise characterization of the non-secular part of the excited-state Hamiltonian of an electronic-nuclear spin system in diamond. The method relies on the investigation of the dynamic nuclear polarization mediated by the electronic spin, which is currently exploited as a primary tool for initializing nuclear qubits and performing enhanced nuclear magnetic resonance. By measuring the temporal evolution of the population of the ground-state hyperfine levels of a nitrogen-vacancy center, we obtain the first direct estimation of the excited-state transverse hyperfine coupling between its electronic and nitrogen nuclear spin. Our method could also be applied to other electron-nuclear spin systems, such as those related to defects in silicon carbide.

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F. Poggiali, P. Cappellaro, N. Fabbri. 2017-06-19. Measurement of the excited-state transverse hyperfine coupling in NV centers via dynamic nuclear polarization. https://doi.org/10.1103/physrevb.95.195308

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