Dressed-State Polarization Transfer between Bright & Dark Spins in Diamond

TL;DR

This paper demonstrates a dressed-state, double-resonance method to transfer polarization from optically accessible NV center spins to dark spins in diamond, enabling potential cooling of spin baths for quantum applications.

Contribution

It introduces a novel polarization transfer technique between bright and dark spins in diamond using dressed-state double-resonance, expanding control over dark spin states.

Findings

Successful polarization transfer from NV to P1 spins.

Potential to cool dark spin baths near zero temperature.

Advancement in quantum sensing and information processing.

Abstract

Under ambient conditions, spin impurities in solid-state systems are found in thermally-mixed states and are optically "dark", i.e., the spin states cannot be optically controlled. Nitrogen-vacancy (NV) centers in diamond are an exception in that the electronic spin states are "bright", i.e., they can be polarized by optical pumping, coherently manipulated with spin-resonance techniques, and read out optically, all at room temperature. Here we demonstrate a dressed-state, double-resonance scheme to transfer polarization from bright NV electronic spins to dark substitutional-Nitrogen (P1) electronic spins in diamond. This polarization-transfer mechanism could be used to cool a mesoscopic bath of dark spins to near-zero temperature, thus providing a resource for quantum information and sensing, and aiding studies of quantum effects in many-body spin systems.