Local and bulk 13C hyperpolarization in NV-centered diamonds at variable fields and orientations

TL;DR

This paper presents a versatile room-temperature method for hyperpolarizing 13C nuclei in diamond NV centers across various magnetic fields and orientations, enhancing NMR and quantum information applications.

Contribution

The authors develop a new approach combining microwave and laser transitions for efficient electron-to-13C spin transfer, independent of magnetic field strength and alignment.

Findings

Achieved efficient 13C hyperpolarization at multiple magnetic fields.

Demonstrated hyperpolarization transfer to both nearby and distant 13C nuclei.

Enabled bulk nuclear polarization in diamond at room temperature.

Abstract

Polarizing nuclear spins is of fundamental importance in biology, chemistry and physics. Methods for hyperpolarizing 13C nuclei from free electrons in bulk, usually demand operation at cryogenic temperatures. Room-temperature approaches targeting diamonds with nitrogen-vacancy (NV) centers could alleviate this need, but hitherto proposed strategies lack generality as they demand stringent conditions on the strength and/or alignment of the magnetic field. We report here an approach for achieving efficient electron->13C spin alignment transfers, compatible with a broad range of magnetic field strengths and field orientations with respect to the diamond crystal. This versatility results from combining coherent microwave- and incoherent laser-induced transitions between selected energy states of the coupled electron-nuclear spin manifold. 13C-detected Nuclear Magnetic Resonance (NMR) experiments demonstrate that this hyperpolarization can be transferred via first-shell or via distant 13Cs, throughout the nuclear bulk ensemble. This method opens new perspectives for applications of diamond NV centers in NMR, and in quantum information processing.