Optical properties of the nitrogen-vacancy singlet levels in diamond

TL;DR

This study investigates the optical characteristics of the 1042 nm transition in negatively-charged NV centers in diamond, revealing details about level coupling, lifetimes, and polarization dependence to better understand their level structure and optical pumping.

Contribution

It provides new experimental insights into the NV center's singlet levels, including their lifetimes, coupling, and polarization properties, advancing understanding of their optical behavior.

Findings

Upper level couples to m_s=+/-1 sublevels of {^3}E state

Lower level has temperature-dependent lifetime (462 ns at 4.4 K, 219 ns at 295 K)

Transition is between A_1 and E orbital characters

Abstract

We report measurements of the optical properties of the 1042 nm transition of negatively-charged Nitrogen-Vacancy (NV) centers in type 1b diamond. The results indicate that the upper level of this transition couples to the m_s=+/-1 sublevels of the {^3}E excited state and is short-lived, with a lifetime <~ 1 ns. The lower level is shown to have a temperature-dependent lifetime of 462(10) ns at 4.4 K and 219(3) ns at 295 K. The light-polarization dependence of 1042 nm absorption confirms that the transition is between orbitals of A_1 and E character. The results shed new light on the NV level structure and optical pumping mechanism.