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

Physical Review Applied

Enhanced Readout and Sensitivity of Diamond N- V Centers Coupled to Hyperbolic Metamaterial Photonic Cavities

Jonathan Bar-David, Sigal A. Wolf, S.R.K. Chaitanya Indukuri, Rotem Malkinson, Noa Mazurski, Uriel Levy, Nir Bar‐Gill

Published Jun 27, 2023• 10 citations
Publisher

Abstract

Nitrogen-vacancy (N-V) centers are diamond lattice defects that may be manipulated and controlled by visible light and microwave irradiation. They are considered a promising solid-state platform for a broad range of quantum technologies, such as magnetic field sensing. A major limitation in realizing such applications is the weak optical signal attained from the NVs, making the readout inefficient and prone to noise. Here, we report the increased brightness and shortened lifetime of N-V centers coupled to hyperbolic metamaterial photonic cavities with optimized dispersion characteristics. As a result, we demonstrate the enhancement of magnetic field sensitivity and measurement SNR. These results introduce a broadly applicable, robust, and technically accessible platform, promising improved performance relevant for a multitude of solid-state defects and their applications.

DOI
10.1103/physrevapplied.19.064074

Related papers

Purcell-enhanced optical spin readout of nitrogen-vacancy centers in diamond

Sigal A. Wolf, Itamar Rosenberg, Ronen Rapaport +1 more

Nitrogen-vacancy (NV) color centers in diamond have emerged as promising quantum solid-state systems, with applications ranging from quantum information processing to magnetic sensing. One of the most useful properties of NVs is the ability to read their ground-state spin projection optically at room temperature. Using theoretical analysis of Purcell-enhanced NV optical coupling, we identify parameters for a significantly enhanced single-to-noise ratio (SNR) of the optical spin-state readout. We then demonstrate that a combined increase in spontaneous emission (through Purcell enhancement) and in optical excitation could significantly increase the readout SNR. Our combined analytical and numerical analysis, which is relevant for various optically active solid-state systems, differentiates between state-mixing processes and provides insights into the optimal light-matter coupling design.

arXiv:1505.01006•Physical Review B•Dec 7, 2015•41 citations

Novel Magnetic-Sensing Modalities with Nitrogen-Vacancy Centers in Diamond

Huijie Zheng, Arne Wickenbrock, Georgios Chatzidrosos +16 more

In modern-day quantum metrology, quantum sensors are widely employed to detect weak magnetic fields or nanoscale signals. Quantum devices, exploiting quantum coherence, are inevitably connected to physical constants and can achieve accuracy, repeatability, and precision approaching fundamental limits. As a result, these sensors have shown utility in a wide range of research domains spanning both science and technology. A rapidly emerging quantum sensing platform employs atomic-scale defects in crystals. In particular, magnetometry using nitrogen-vacancy (NV) color centers in diamond has garnered increasing interest. NV systems possess a combination of remarkable properties, optical addressability, long coherence times, and biocompatibility. Sensors based on NV centers excel in spatial resolution and magnetic sensitivity. These diamond-based sensors promise comparable combination of high spatial resolution and magnetic sensitivity without cryogenic operation. The above properties of NV magnetometers promise increasingly integrated quantum measurement technology, as a result, they have been extensively developed with various protocols and find use in numerous applications spanning materials characterization, nuclear magnetic resonance (NMR), condensed matter physics, paleomagnetism, neuroscience and living systems biology, and industrial vector magnetometry. In this chapter, NV centers are explored for magnetic sensing in a number of contexts. In general, we introduce novel regimes for magnetic-field probes with NV ensembles. Specifically, NV centers are developed for sensitive magnetometers for applications where microwaves (MWs) are prohibitively invasive and operations need to be carried out under zero ambient magnetic field. The primary goal of our discussion is to improve the utility of these NV center-based magnetometers.

IntechOpen eBooks•Feb 8, 2021•1 citation

Dispersive readout of cavity-coupled solid-state sensor with near-unity readout fidelity

Hanfeng Wang, Shuang Wu, Matthew E. Trusheim +2 more

Solid-state quantum sensors based on ensembles of nitrogen-vacancy (NV) centers in diamond have emerged as powerful platforms for high-precision metrology. Coupling the NV ensemble to a microwave cavity mode in a cavity quantum electrodynamics (cQED) configuration enables spin readout that surpasses the limitations of conventional optical detection, achieving sub-picotesla magnetic sensitivities. However, existing continuous-wave cQED approaches remain far from the intrinsic spin-projection-noise limit due to spin saturation and power broadening. Here, we introduce a dispersive cQED readout technique to overcome these fundamental limitations in NV ensemble sensing. We develop a comprehensive theoretical framework describing the dispersive interaction and analyze the time-domain dynamics of a strongly-coupled NV-cavity system. Our results indicate near-unity inverse readout fidelity and femtotesla-level sensitivity using a commercially available diamond NV ensemble. Importantly, the dispersive readout exhibits a distinct sensitivity scaling that improves as 1/N with increasing number of spins N, providing a practical pathway toward approaching the standard quantum limit for solid-state spin-ensemble sensors.

quant-pharXiv:2605.25152•May 26, 2026•0 citations

Initialization and measurement of nitrogen-vacancy centers in diamond with plasmonic Purcell enhancement

Sigal A. Wolf, Itamar Rosenberg, Ronen Rapaport +1 more

Nitrogen-Vacancy (NV) color centers in diamond have emerged as promising quantum solid-state systems, with applications ranging from quantum information processing to magnetic sensing. One of the most useful properties of NVs is the ability to read their ground-state spin projection optically at room temperature. In this work we consider the effect of the Purcell enhancement on the ability to initialize the NV state and analyze the effect to imperfect initialization on the measurement SNR. We demonstrate that even with feasible initial conditions the combined increase in spontaneous emission (through Purcell enhancement) and in optical excitation could significantly increase the readout SNR.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Apr 29, 2016•0 citations

Multicone Diamond Waveguides for Nanoscale Quantum Sensing

Tianqi Zhu, J. Rhensius, Konstantin Herb +4 more

The long-lived electronic spin of the nitrogen-vacancy (NV) center in diamonds is a promising quantum sensor for detecting nanoscopic magnetic and electric fields in various environments. However, the poor signal-to-noise ratio (SNR) of prevalent optical spin-readout techniques presents a critical challenge in improving measurement sensitivity. Here, we address this limitation by coupling individual NVs to optimized diamond nanopillars, thereby enhancing the collection efficiency of fluorescence. Guided by near-field optical simulations, we predict improved performance for tall (≥5 μm) pillars with tapered sidewalls. This is subsequently verified by fabricating and characterizing a representative set of structures using a newly developed nanofabrication process. We observe increased SNR for optimized devices, owing to improved emission collimation and directionality. Promisingly, these devices are compatible with low-numerical-aperture collection optics and a reduced tip radius, reducing experimental overhead and facilitating improved spatial resolution for scanning applications.

arXiv:2306.02966•Nano Letters•Nov 7, 2023•19 citations

Tailoring of measurement protocols for biomagnetic signals using quantum optimal control on NV centers in diamond

Isabell Jauch, Thomas Strohm, Tino Fuchs +1 more

Nitrogen-vacancy (NV) centers in diamond are a promising platform for ambient, high-spatial resolution magnetometry relevant to biological signals such as cardiac and muscle activity. One of the challenges is the development of pulse sequences tailored to biological signals in the near DC-range. The spatial environment of NV centers within the diamond lattice is highly complex, e.g. due to magnetic field inhomogeneities, limiting the sensors performance. To overcome these experimental constraints, quantum optimal control (QOC) aims at a precise manipulation of the systems dynamics via optimally shaped microwave pulses increasing the overall robustness of spin-based quantum sensors.

Optical and Quantum Sensing and Precision Metrology II•Mar 5, 2026•0 citations
Nitrogen-vacancy (N-V) centers are diamond lattice defects that may be manipulated and controlled by visible light and microwave irradiation. They are considered a promising solid-state platform for a broad range of quantum technologies, such as magnetic field sensing. A major limitation in realizing such applications is the weak optical signal attained from the NVs, making the readout inefficient and prone to noise. Here, we report the increased brightness and shortened lifetime of N-V centers coupled to hyperbolic metamaterial photonic cavities with optimized dispersion characteristics. As a result, we demonstrate the enhancement of magnetic field sensitivity and measurement SNR. These results introduce a broadly applicable, robust, and technically accessible platform, promising improved performance relevant for a multitude of solid-state defects and their applications.
Nitrogen-vacancy (NV) color centers in diamond have emerged as promising quantum solid-state systems, with applications ranging from quantum information processing to magnetic sensing. One of the most useful properties of NVs is the ability to read their ground-state spin projection optically at room temperature. Using theoretical analysis of Purcell-enhanced NV optical coupling, we identify parameters for a significantly enhanced single-to-noise ratio (SNR) of the optical spin-state readout. We then demonstrate that a combined increase in spontaneous emission (through Purcell enhancement) and in optical excitation could significantly increase the readout SNR. Our combined analytical and numerical analysis, which is relevant for various optically active solid-state systems, differentiates between state-mixing processes and provides insights into the optimal light-matter coupling design.
In modern-day quantum metrology, quantum sensors are widely employed to detect weak magnetic fields or nanoscale signals. Quantum devices, exploiting quantum coherence, are inevitably connected to physical constants and can achieve accuracy, repeatability, and precision approaching fundamental limits. As a result, these sensors have shown utility in a wide range of research domains spanning both science and technology. A rapidly emerging quantum sensing platform employs atomic-scale defects in crystals. In particular, magnetometry using nitrogen-vacancy (NV) color centers in diamond has garnered increasing interest. NV systems possess a combination of remarkable properties, optical addressability, long coherence times, and biocompatibility. Sensors based on NV centers excel in spatial resolution and magnetic sensitivity. These diamond-based sensors promise comparable combination of high spatial resolution and magnetic sensitivity without cryogenic operation. The above properties of NV magnetometers promise increasingly integrated quantum measurement technology, as a result, they have been extensively developed with various protocols and find use in numerous applications spanning materials characterization, nuclear magnetic resonance (NMR), condensed matter physics, paleomagnetism, neuroscience and living systems biology, and industrial vector magnetometry. In this chapter, NV centers are explored for magnetic sensing in a number of contexts. In general, we introduce novel regimes for magnetic-field probes with NV ensembles. Specifically, NV centers are developed for sensitive magnetometers for applications where microwaves (MWs) are prohibitively invasive and operations need to be carried out under zero ambient magnetic field. The primary goal of our discussion is to improve the utility of these NV center-based magnetometers.
Solid-state quantum sensors based on ensembles of nitrogen-vacancy (NV) centers in diamond have emerged as powerful platforms for high-precision metrology. Coupling the NV ensemble to a microwave cavity mode in a cavity quantum electrodynamics (cQED) configuration enables spin readout that surpasses the limitations of conventional optical detection, achieving sub-picotesla magnetic sensitivities. However, existing continuous-wave cQED approaches remain far from the intrinsic spin-projection-noise limit due to spin saturation and power broadening. Here, we introduce a dispersive cQED readout technique to overcome these fundamental limitations in NV ensemble sensing. We develop a comprehensive theoretical framework describing the dispersive interaction and analyze the time-domain dynamics of a strongly-coupled NV-cavity system. Our results indicate near-unity inverse readout fidelity and femtotesla-level sensitivity using a commercially available diamond NV ensemble. Importantly, the dispersive readout exhibits a distinct sensitivity scaling that improves as 1/N with increasing number of spins N, providing a practical pathway toward approaching the standard quantum limit for solid-state spin-ensemble sensors.
Nitrogen-Vacancy (NV) color centers in diamond have emerged as promising quantum solid-state systems, with applications ranging from quantum information processing to magnetic sensing. One of the most useful properties of NVs is the ability to read their ground-state spin projection optically at room temperature. In this work we consider the effect of the Purcell enhancement on the ability to initialize the NV state and analyze the effect to imperfect initialization on the measurement SNR. We demonstrate that even with feasible initial conditions the combined increase in spontaneous emission (through Purcell enhancement) and in optical excitation could significantly increase the readout SNR.
The long-lived electronic spin of the nitrogen-vacancy (NV) center in diamonds is a promising quantum sensor for detecting nanoscopic magnetic and electric fields in various environments. However, the poor signal-to-noise ratio (SNR) of prevalent optical spin-readout techniques presents a critical challenge in improving measurement sensitivity. Here, we address this limitation by coupling individual NVs to optimized diamond nanopillars, thereby enhancing the collection efficiency of fluorescence. Guided by near-field optical simulations, we predict improved performance for tall (≥5 μm) pillars with tapered sidewalls. This is subsequently verified by fabricating and characterizing a representative set of structures using a newly developed nanofabrication process. We observe increased SNR for optimized devices, owing to improved emission collimation and directionality. Promisingly, these devices are compatible with low-numerical-aperture collection optics and a reduced tip radius, reducing experimental overhead and facilitating improved spatial resolution for scanning applications.
Nitrogen-vacancy (NV) centers in diamond are a promising platform for ambient, high-spatial resolution magnetometry relevant to biological signals such as cardiac and muscle activity. One of the challenges is the development of pulse sequences tailored to biological signals in the near DC-range. The spatial environment of NV centers within the diamond lattice is highly complex, e.g. due to magnetic field inhomogeneities, limiting the sensors performance. To overcome these experimental constraints, quantum optimal control (QOC) aims at a precise manipulation of the systems dynamics via optimally shaped microwave pulses increasing the overall robustness of spin-based quantum sensors.