Quenching nitrogen-vacancy center photoluminescence with infrared pulsed laser

TL;DR

This paper demonstrates that infrared pulsed laser can reversibly quench the photoluminescence of nitrogen-vacancy centers in diamond nanocrystals, enabling fast, sub-diffraction imaging by controlling emission with a shaped IR beam.

Contribution

It introduces a novel IR pulsed laser technique to control NV center photoluminescence, facilitating super-resolution imaging of diamond nanocrystals.

Findings

IR laser achieves ~90% quenching of NV photoluminescence.

Quenching is reversible with response time of hundreds of picoseconds.

Method enables sub-diffraction imaging using shaped IR beams.

Abstract

Diamond nanocrystals containing Nitrogen-Vacancy (NV) color centers have been used in recent years as fluorescent probes for near-field and cellular imaging. In this work we report that an infrared (IR) pulsed excitation beam can quench the photoluminescence of NV color center in a diamond nanocrystal (size < 50 nm) with an extinction ratio as high as ~90%. We attribute this effect to the heating of the nanocrystal consecutive to multi-photon absorption by the diamond matrix. This quenching is reversible: the photoluminescence intensity goes back to its original value when the IR laser beam is turned off, with a typical response time of hundred picoseconds, allowing for a fast control of NV color center photoluminescence. We used this effect to achieve sub-diffraction limited imaging of fluorescent diamond nanocrystals on a coverglass. For that, as in Ground State Depletion super-resolution technique, we combined the green excitation laser beam with the control IR depleting one after shaping its intensity profile in a doughnut form, so that the emission comes only from the sub-wavelength size central part.