Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Applied Physics Letters

Detection of nanowatt microwave radiation by the photoluminescence of an ensemble of negatively charged nitrogen vacancies in diamond

J. Debus, Vitalii Yu. Ivanov, D. Braukmann, Д. В. Азамат, Evan R. Glaser, Thomas A. Kennedy, Dmitri R. Yakovlev, M. Bayer

Published Nov 5, 2018• 4 citations
Publisher

Abstract

We report on detecting continuous 60-GHz microwave radiation with powers in the nanowatt range by the photoluminescence of an ensemble of negatively charged nitrogen vacancy (NV−) centers in diamond at room temperature. The high contrast of the optically detected magnetic resonance and the efficient photon collection yield a magnetic field sensitivity of 86 nT/Hz for continuous-wave laser excitation with a photon energy of 2.33 eV and a power density of 93 W/cm2. The efficiency of the microwave-power-to-magnetic-field conversion amounts to 0.54 mT/W. The microwave excitation also enhances the degree of the linear polarization of NV− photoluminescence at magnetic resonance conditions, and for linearly co-polarized NV− photoluminescence and laser light, the magnetic field sensitivity is improved by about 7%.

DOI
10.1063/1.5053639

Related papers

Effects of Microwave and Laser Power on Optical Detection Magnetic Resonance of Diamond Nitrogen Vacancy Center

Qiang Song, Yang Lu, Dingqu Zhang +3 more

Using continuous wave optical detection magnetic resonance (ODMR), diamond nitrogen-vacancy (NV) center has been widely used in magnetic field measurement at the experimental stage. Microwave and laser power have significant influence on the sensitivity of magnetic field measurement. A set of confocal magnetic field detection system based on the ensemble of NV center is established. By adjusting the microwave and laser power, it is observed that the contrast and the full width at half maximum (FWHM) of the ODMR spectra change obviously. The experiment indicates that the contrast has a maximum value under the change of microwave and laser power, while the FWHM is mainly dominated by microwave power at low light intensity. Adjusting the microwave power to obtain an applicable FWHM, then reducing the laser power appropriately, the light narrowing phenomenon could be observed, and the operation above could improve the sensitivity of magnetic field measurement effectively.

•Sep 15, 2023•1 citation

Using NV centers in diamond to detect DC to very-low frequency magnetic fields

Valts Krumins, Ivars Krastins, Oskars Rudzitis +3 more

In this work we present a compact and portable tabletop magnetometer that utilizes negatively charged nitrogen-vacancy (NV) centers in diamond. The magnetometer is operated using a dual microwave resonance detection approach in combination with an optically detected magnetic resonance (ODMR) technique (mitigating drifts in results due to changes of the diamond temperature), capable of simultaneously exciting and registering two ODMR transitions. The experimentally measured magnetic field noise-floor is $\approx 2.3~\textrm{nT}\sqrt{\textrm{Hz}}$ while the calculated shot-noise-limited magnetic field sensitivity is $\approx 585~\textrm{pT}\sqrt{\textrm{Hz}}$ when excited with a continuous wave laser at 0.5~W. These results pave the way for realizing a simple set-up magnetometer for precise single axis magnetic field measurements for example for accurate electric current measurements for stabilization purposes and magnetic communication applications.

quant-pharXiv:2512.24273•Dec 31, 2025

Laser-induced thermal effects on ODMR in NV-ensemble diamond at ambient and vacuum

Mohammed Attrash, Tamara Amro, Ilya Simanovsky +5 more

The spin dynamics of the negatively charged nitrogen-vacancy (NV⁻) centers in diamond are highly sensitive to quantum electromagnetic fluctuations arising from optical excitation, chemical interactions, and thermal processes. Here we investigated the optical and spin properties of ensembles of NV⁻ centers in diamond under continuous-wave (CW) and nanosecond pulsed laser excitation. Optical detection of magnetic resonance (ODMR) is employed to monitor laser induced shifts of the zero-field splitting parameter D under ambient and high-vacuum conditions. Increasing CW laser power results in a systematic downshift of the resonance frequency due to laser-induced heating. The effect is significantly enhanced under vacuum, where the shift in D reaches up to ~17 MHz, compared to ~5 MHz in air, emphasizing the role of environmental thermal dissipation. Under nanosecond pulsed excitation, increasing the pulse repetition rate similarly leads to resonance shifts and reduced ODMR contrast, consistent with cumulative thermal effects. Visible and infrared spectroscopy confirm power dependent modifications of NV emission. Time resolved photoluminescence measurements showed that the excited-state lifetime (~6 ns) remains nearly constant across the investigated excitation range, indicating that in this regime the dominant limitation is thermal loading of the spin resonance rather than a change in intrinsic radiative decay dynamics. These results provide a comprehensive characterization of thermal effects in high power optical excitation of NV ensembles and are directly relevant for high intensity NV-based sensing and spectroscopy, particularly in vacuum environments.

Diamond and Related Materials•Mar 26, 2026•0 citations

Real-Time Magnetic Field Sensing based on Microwave Frequency Modulated Photocurrent of Nitrogen-Vacancy Centers in Diamond

Xuan-Ming Shen, Qilong Wu, Huihui Yu +6 more

While photoelectric detection of magnetic resonance (PDMR) can be applied to miniaturize nitrogen-vacancy (NV) center-based quantum sensors, real demonstration of PDMR-based magnetic field sensing remains as a distinctive challenge. To tackle this challenge, in this article, we fabricate diamond samples with electrodes and microwave antenna on the surface, and realize PDMR by detecting photocurrent in picoampere range via various lock-in amplifying modes. We obtain a theoretical and experimental sensitivity 397 nT/Hz and 921 nT/Hz of magnetic field detection in DC-10 Hz range with a laser intensity and microwave frequency modulation mode, respectively, and demonstrate for the first time, a real-time tracking of alternating magnetic field with a standard deviation of 1.5 uT. Furthermore, we investigate systematically the dependence of the PDMR contrast, linewidth and the sensitivity on the laser and microwave power, and find a perfect agreement with a master equation-based theory. Thus, our results represent a critical step forward in transitioning PDMR from a spectroscopic technique to a practical sensing modality.

quant-pharXiv:2602.07926•Feb 10, 2026

High-contrast absorption magnetometry in the visible to near-infrared range with nitrogen-vacancy ensembles

Florian Schall, Felix A. Hahl, Lukas Lindner +6 more

Magnetometry with nitrogen-vacancy (NV) centers in diamond has so far been measured via emission of light from NV centers or via absorption at the singlet transition at 1042 nm. Here, we demonstrate a phenomenon of broadband optical absorption by the NV centers starting in the emission wavelength and reaching up to 1000 nm. The measurements are enabled by a high-finesse cavity, which is used for room-temperature continuous wave pump-probe experiments. The red to infrared probe beam shows the typical optically detected magnetic resonance (ODMR) signal of the NV spin with contrasts up to 42 %. This broadband optical absorption has not yet been reported in terms of NV magnetometry. We argue that the lower level of the absorbing transition could be the energetically lower NV singlet state, based on the increased optical absorption for a resonant microwave field and the spectral behavior. Investigations of the photon-shot-noise-limited sensitivity show improvements with increasing probe wavelength, reaching an optimum of 7.5pT/Hz. The results show significantly improved ODMR contrast compared to emission-based magnetometry. This opens a new detection wavelength regime with coherent laser signal detection for high-sensitivity NV magnetometry.

Optics Express•Jan 23, 2025•2 citations

Magnetic-field-dependent stimulated emission from nitrogen-vacancy centers in diamond

Felix A. Hahl, Lukas Lindner, Xavier Vidal +9 more

Negatively charged nitrogen-vacancy (NV) centers in diamond are promising magnetic field quantum sensors. Laser threshold magnetometry theory predicts improved NV center ensemble sensitivity via increased signal strength and magnetic field contrast. Here, we experimentally demonstrate laser threshold magnetometry. We use a macroscopic high-finesse laser cavity containing a highly NV-doped and low absorbing diamond gain medium that is pumped at 532 nm and resonantly seeded at 710 nm. This enables a 64% signal power amplification by stimulated emission. We test the magnetic field dependency of the amplification and thus demonstrate magnetic field-dependent stimulated emission from an NV center ensemble. This emission shows an ultrahigh contrast of 33% and a maximum output power in the milliwatt regime. The coherent readout of NV centers pave the way for novel cavity and laser applications of quantum defects and diamond NV magnetic field sensors with substantially improved sensitivity for the health, research, and mining sectors.

Science Advances•Jun 3, 2022•44 citations
We report on detecting continuous 60-GHz microwave radiation with powers in the nanowatt range by the photoluminescence of an ensemble of negatively charged nitrogen vacancy (NV−) centers in diamond at room temperature. The high contrast of the optically detected magnetic resonance and the efficient photon collection yield a magnetic field sensitivity of 86 nT/Hz for continuous-wave laser excitation with a photon energy of 2.33 eV and a power density of 93 W/cm2. The efficiency of the microwave-power-to-magnetic-field conversion amounts to 0.54 mT/W. The microwave excitation also enhances the degree of the linear polarization of NV− photoluminescence at magnetic resonance conditions, and for linearly co-polarized NV− photoluminescence and laser light, the magnetic field sensitivity is improved by about 7%.
Using continuous wave optical detection magnetic resonance (ODMR), diamond nitrogen-vacancy (NV) center has been widely used in magnetic field measurement at the experimental stage. Microwave and laser power have significant influence on the sensitivity of magnetic field measurement. A set of confocal magnetic field detection system based on the ensemble of NV center is established. By adjusting the microwave and laser power, it is observed that the contrast and the full width at half maximum (FWHM) of the ODMR spectra change obviously. The experiment indicates that the contrast has a maximum value under the change of microwave and laser power, while the FWHM is mainly dominated by microwave power at low light intensity. Adjusting the microwave power to obtain an applicable FWHM, then reducing the laser power appropriately, the light narrowing phenomenon could be observed, and the operation above could improve the sensitivity of magnetic field measurement effectively.
In this work we present a compact and portable tabletop magnetometer that utilizes negatively charged nitrogen-vacancy (NV) centers in diamond. The magnetometer is operated using a dual microwave resonance detection approach in combination with an optically detected magnetic resonance (ODMR) technique (mitigating drifts in results due to changes of the diamond temperature), capable of simultaneously exciting and registering two ODMR transitions. The experimentally measured magnetic field noise-floor is ≈2.3 nTHz\approx 2.3~\textrm{nT}\sqrt{\textrm{Hz}}≈2.3 nTHz​ while the calculated shot-noise-limited magnetic field sensitivity is ≈585 pTHz\approx 585~\textrm{pT}\sqrt{\textrm{Hz}}≈585 pTHz​ when excited with a continuous wave laser at 0.5~W. These results pave the way for realizing a simple set-up magnetometer for precise single axis magnetic field measurements for example for accurate electric current measurements for stabilization purposes and magnetic communication applications.
The spin dynamics of the negatively charged nitrogen-vacancy (NV⁻) centers in diamond are highly sensitive to quantum electromagnetic fluctuations arising from optical excitation, chemical interactions, and thermal processes. Here we investigated the optical and spin properties of ensembles of NV⁻ centers in diamond under continuous-wave (CW) and nanosecond pulsed laser excitation. Optical detection of magnetic resonance (ODMR) is employed to monitor laser induced shifts of the zero-field splitting parameter D under ambient and high-vacuum conditions. Increasing CW laser power results in a systematic downshift of the resonance frequency due to laser-induced heating. The effect is significantly enhanced under vacuum, where the shift in D reaches up to ~17 MHz, compared to ~5 MHz in air, emphasizing the role of environmental thermal dissipation. Under nanosecond pulsed excitation, increasing the pulse repetition rate similarly leads to resonance shifts and reduced ODMR contrast, consistent with cumulative thermal effects. Visible and infrared spectroscopy confirm power dependent modifications of NV emission. Time resolved photoluminescence measurements showed that the excited-state lifetime (~6 ns) remains nearly constant across the investigated excitation range, indicating that in this regime the dominant limitation is thermal loading of the spin resonance rather than a change in intrinsic radiative decay dynamics. These results provide a comprehensive characterization of thermal effects in high power optical excitation of NV ensembles and are directly relevant for high intensity NV-based sensing and spectroscopy, particularly in vacuum environments.
While photoelectric detection of magnetic resonance (PDMR) can be applied to miniaturize nitrogen-vacancy (NV) center-based quantum sensors, real demonstration of PDMR-based magnetic field sensing remains as a distinctive challenge. To tackle this challenge, in this article, we fabricate diamond samples with electrodes and microwave antenna on the surface, and realize PDMR by detecting photocurrent in picoampere range via various lock-in amplifying modes. We obtain a theoretical and experimental sensitivity 397 nT/Hz and 921 nT/Hz of magnetic field detection in DC-10 Hz range with a laser intensity and microwave frequency modulation mode, respectively, and demonstrate for the first time, a real-time tracking of alternating magnetic field with a standard deviation of 1.5 uT. Furthermore, we investigate systematically the dependence of the PDMR contrast, linewidth and the sensitivity on the laser and microwave power, and find a perfect agreement with a master equation-based theory. Thus, our results represent a critical step forward in transitioning PDMR from a spectroscopic technique to a practical sensing modality.
Magnetometry with nitrogen-vacancy (NV) centers in diamond has so far been measured via emission of light from NV centers or via absorption at the singlet transition at 1042 nm. Here, we demonstrate a phenomenon of broadband optical absorption by the NV centers starting in the emission wavelength and reaching up to 1000 nm. The measurements are enabled by a high-finesse cavity, which is used for room-temperature continuous wave pump-probe experiments. The red to infrared probe beam shows the typical optically detected magnetic resonance (ODMR) signal of the NV spin with contrasts up to 42 %. This broadband optical absorption has not yet been reported in terms of NV magnetometry. We argue that the lower level of the absorbing transition could be the energetically lower NV singlet state, based on the increased optical absorption for a resonant microwave field and the spectral behavior. Investigations of the photon-shot-noise-limited sensitivity show improvements with increasing probe wavelength, reaching an optimum of 7.5pT/Hz. The results show significantly improved ODMR contrast compared to emission-based magnetometry. This opens a new detection wavelength regime with coherent laser signal detection for high-sensitivity NV magnetometry.
Negatively charged nitrogen-vacancy (NV) centers in diamond are promising magnetic field quantum sensors. Laser threshold magnetometry theory predicts improved NV center ensemble sensitivity via increased signal strength and magnetic field contrast. Here, we experimentally demonstrate laser threshold magnetometry. We use a macroscopic high-finesse laser cavity containing a highly NV-doped and low absorbing diamond gain medium that is pumped at 532 nm and resonantly seeded at 710 nm. This enables a 64% signal power amplification by stimulated emission. We test the magnetic field dependency of the amplification and thus demonstrate magnetic field-dependent stimulated emission from an NV center ensemble. This emission shows an ultrahigh contrast of 33% and a maximum output power in the milliwatt regime. The coherent readout of NV centers pave the way for novel cavity and laser applications of quantum defects and diamond NV magnetic field sensors with substantially improved sensitivity for the health, research, and mining sectors.