Wavelength Dependence of the Electrical and Optical Readout of NV Centers in Diamond

TL;DR

This study investigates how the electrical and optical readout contrast of NV centers in diamond varies with excitation wavelength, revealing optimal conditions for enhanced detection efficiency.

Contribution

It provides new insights into wavelength-dependent contrast behavior, identifying specific wavelengths that maximize electrical and optical readout contrast of NV centers.

Findings

Optical contrast peaks between 480-580 nm.

Electrical contrast is maximized at 575 nm for NV$^0$ zero-phonon line.

Enhanced EDMR observed at 521 nm, indicating possible excited states.

Abstract

We study the contrast for electrical and optical readout of NV centers in diamond in dependence of the optical excitation wavelength using different excitation schemes. While the optically detected magnetic resonance (ODMR) works efficiently between 480 and 580 nm, electrically detected magnetic resonance (EDMR) shows a strong dependence on the excitation dynamics. The highest, electrically detected contrast of -23% is achieved by resonantly exciting the zero-phonon line of the neutral charge state of NV at 575 nm. EDMR is also enhanced at 521 nm, possibly due to a further excited state of NV$^-$.