Decoupling Nuclear Spins via Interaction-Induced Freezing in Nitrogen Vacancy Centers in Diamond

TL;DR

This paper introduces a protocol to freeze and isolate the nuclear spin in NV centers, enhancing quantum memory stability by shielding it from environmental noise through interaction-induced effects.

Contribution

The authors propose a novel freezing protocol that decouples the nuclear spin from noise in NV centers using unequal Rabi driving, supported by numerical simulations.

Findings

Effective shielding of nuclear spins from noise demonstrated

Suppression of quantum correlations observed during freezing

Potential for extending quantum memory coherence times

Abstract

Nitrogen-Vacancy (NV) centers in diamonds provide a room-temperature platform for various emerging quantum technologies, e.g. the long nuclear spin coherence times as potential quantum memory registers. We demonstrate a freezing protocol for an NV center to isolate its intrinsic nuclear spin from a noisy electromagnetic environment. Any initial state of the nuclear spin can be frozen when the hyperfine-coupled electron and nuclear spins are simultaneously driven with unequal Rabi frequencies. Through numerical simulations, we show that our protocol can effectively shield the nuclear spin from strong drive or noise fields. We also observe a clear suppression of quantum correlations in the frozen nuclear spin regime by measuring the quantum discord of the electron-nuclear spin system. These features can be instrumental in extending the storage times of NV nuclear-spin based quantum memories in hybrid quantum systems.