Spin dynamics in the optical cycle of single nitrogen-vacancy centres in diamond

TL;DR

This study provides a detailed understanding of the spin-dependent decay processes and intersystem crossing in the optical cycle of single NV centres in diamond, crucial for quantum applications.

Contribution

It offers a comprehensive measurement of spin-resolved lifetimes, spin-flip probabilities, and intersystem crossing dynamics in NV centres, advancing knowledge of their spin-dependent optical processes.

Findings

Determined spin-resolved excited state lifetimes.

Measured spin-flip probabilities per optical cycle.

Analyzed temperature dependence of singlet decay rates.

Abstract

We investigate spin-dependent decay and intersystem crossing in the optical cycle of single negatively-charged nitrogen-vacancy (NV) centres in diamond. We use spin control and pulsed optical excitation to extract both the spin-resolved lifetimes of the excited states and the degree of optically-induced spin polarization. By optically exciting the centre with a series of picosecond pulses, we determine the spin-flip probabilities per optical cycle, as well as the spin-dependent probability for intersystem crossing. This information, together with the indepedently measured decay rate of singlet population provides a full description of spin dynamics in the optical cycle of NV centres. The temperature dependence of the singlet population decay rate provides information on the number of singlet states involved in the optical cycle.