Nonlinear optical charge-state switching and pumping to dark state of a diamond nitrogen-vacancy center
Year: 2026
Type: article
Abstract: The photodynamics of diamond nitrogen-vacancy (NV) centers limits their performance in many quantum technologies. Quenching of photoluminescence, which degrades NV readout, is commonly ascribed to a dark state that is not fully understood. Using a nanoscale cavity to generate intense infrared fields that quench NV emission nonlinearly with field intensity, we show that the dark state is accessed by two-photon pumping into the $^4\!A_2$ quartet state of the neutrally charged NV (NV$^0$). We constrain this state's energy relative to the NV$^0$ ground-state ($^2\!E$) to ${<}0.58$\,eV and the recombination energy threshold to the NV$^-$ ground state ($^3\!A_2$) to $\leq2.33\,\text{eV}$. Furthermore, we estimate the intrinsic lifetime of $^4\!A_2$ state to be $1.78-6.06\,μ\text{s}$ and show that accessing this state allows sensing of local infrared fields. This new understanding will allow predictions of the limits of NV technologies reliant upon intense fields, including levitated systems, spin--optomechanical devices, and absorption--based magnetometers.
Source: Physical Review Letters
DOI: 10.1103/fjhl-yd66
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4404570041