Polarization-selective excitation of N-V centers in diamond

TL;DR

This paper demonstrates polarization-selective microwave excitation of N-V centers in diamond, enabling independent spin transition addressing and rapid orientation identification, which advances quantum information applications.

Contribution

It introduces a resonator for circularly polarized microwaves to study polarization selection rules and applies this to both ensemble and individual N-V centers.

Findings

Polarization selection rules are confirmed for N-V centers.

A rapid optical polarization-based imaging technique is developed.

The method enables orientation-specific spin control at zero magnetic field.

Abstract

The nitrogen-vacancy (N-V) center in diamond is promising as an electron spin qubit due to its long-lived coherence and optical addressability. The ground state is a spin triplet with two levels ($m_s = \pm 1$) degenerate at zero magnetic field. Polarization-selective microwave excitation is an attractive method to address the spin transitions independently, since this allows operation down to zero magnetic field. Using a resonator designed to produce circularly polarized microwaves, we have investigated the polarization selection rules of the N-V center. We first apply this technique to N-V ensembles in [100] and [111]-oriented samples. Next, we demonstrate an imaging technique, based on optical polarization dependence, that allows rapid identification of the orientations of many single N-V centers. Finally, we test the microwave polarization selection rules of individual N-V centers of known orientation.