Towards Quantum Sensing of Chiral-Induced Spin Selectivity: Probing Donor-Bridge-Acceptor Molecules with NV Centers in Diamond

TL;DR

This paper proposes a quantum sensing method using NV centers in diamond to directly measure spin polarization in chiral-induced spin selectivity (CISS) phenomena within donor-bridge-acceptor molecules, aiming to clarify CISS's role in electron transfer.

Contribution

It introduces a novel quantum sensing scheme employing NV centers to detect spin polarization in radical pairs, enabling enantioselective detection at the single-molecule level.

Findings

Demonstrates how Lee-Goldburg decoupling preserves spin polarization.

Proposes a method for enantioselective detection of CISS effects.

Provides a pathway for direct measurement of spin effects in electron transfer.

Abstract

Photoexcitable donor-bridge-acceptor (D-B-A) molecules that support intramolecular charge transfer are ideal platforms to probe the influence of chiral-induced spin selectivity (CISS) in electron transfer and resulting radical pairs. In particular, the extent to which CISS influences spin polarization or spin coherence in the initial state of spin-correlated radical pairs following charge transfer through a chiral bridge remains an open question. Here, we introduce a quantum sensing scheme to measure directly the hypothesized spin polarization in radical pairs using shallow nitrogen-vacancy (NV) centers in diamond at the single- to few-molecule level. Importantly, we highlight the perturbative nature of the electron spin-spin dipolar coupling within the radical pair, and demonstrate how Lee-Goldburg decoupling can preserve spin polarization in D-B-A molecules for enantioselective detection by a single NV center. The proposed measurements will provide fresh insight into spin selectivity in electron transfer reactions.