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

Constructing an Autocorrelation System to Identify Single Nitrogen Vacancy Centers in Diamond

Eunice Y. Paik

Published Jan 1, 2015• 0 citations
OpenAlex

Abstract

The nitrogen-vacancy (NV) center is a defect in the structure of diamond, roughly the size of a single atom, that possesses properties that make it applicable to quantum information processing, high-resolution magnetic resonance imaging, and probing biological systems. When an NV center is excited by green light of wavelength 523 nm, it emits red light of in the range from 600-800 nm tens of nanoseconds later. A confocal microscope can be used to excite and collect emitted photons from NV centers. By detecting the intensity of the emitted red photons, we can determine the quantum state of a single NV center, which is needed to build various quantum computing, sensing and imaging devices. The autocorrelation method is used to detect antibunching in the emission of red photons and ascertain that the observed photons are being emitted from a single NV center. We have built an autocorrelation device that measures, with sub-nanosecond accuracy, the statistical distribution of the arrival times of the red photons emitted from a diamond sample at a photon counter. The device can measure fixed time values with a time resolution of 120 ps FWHM. For uncorrelated sources measured for 120 seconds at the TAC full range of 100 ns, the average counts in each histogram bin were about 0.01% of the predicted value. The autocorrelation device that we have built costs about 10 times less than commercial units used by other NV researchers.

Related papers

An experimental study of diamond and the nitrogen vacancy centre as a source of single photons.

Malehlohonolo. Semonyo

For applications in Quantum Information and Quantum Key Distribution an on-demand source of single photons is desirable because absolute security is of utmost importance. Photons are quantum systems; hence encoding information onto them offers a secure alternative to classical cryptography as a measurement cannot be performed on photons without altering their properties. The Nitrogen Vacancy (NV) centre in diamond is a good source of such photons. It is photo-stable and its location in diamond offers robustness. It has zero phonon line at 637 nm and its relative short luminescence life-time of about 12 ns makes it suitable for generating single photons. This thesis covers two aspects: Firstly the characterization of defects in diamonds and subsequent selection of diamonds suitable for use in the single photon setup and secondly, the development of the experimental setup for single photon generation. This thesis sets out to describe the development of a laboratory based single photon source using the NV centre in diamond. For this purpose a suite of diamond samples were selected and subjected to various spectroscopic tests in order to characterize and classify the samples, especially the presence of the NV centres and their concentrations. The characterization of the defects was done through the use of the following spectroscopic techniques: UltravioletVisible-Near infrared spectroscopy, Infrared spectroscopy, Electron Spin Resonance and Photoluminescence. These techniques enabled us to understand the types and origins of crystal defects that were present in the diamond samples used in this study and to use this to select diamonds that are most suitable for use in generation of single photons. The experimental setup for single photon generation using the NV centre is based on a confocal microscope arrangement. Single NV centres were identified by measuring the second order autocorrelation function of the fluorescence light emitted by the sample when illuminated with a laser. This measurement was done using a Hanbury-Brown Twiss (HBT) interferometer.

•Jan 1, 2009•0 citations

A single photon source based on NV centers in diamond nanocrystals

Juliane Bahe, Xiaoqing Zhou, Tobias Jan Kippenberg +4 more

The development of reliable devices to generate single photons is crucial for applications in quantum cryptography, as well as for fundamental quantum optics experiments. Due to their extremely high photostability at room temperature, optically active defects in solids, the so called color centers, are among the most promising candidates. Single NV (nitrogen-vacancy) centers in diamond have been demonstrated to be able to generate single photons and have already shown advantages compared to attenuated laser pulses in a quantum cryptography experiment. The nitrogen-vacancy center (NV center) in diamond consists of a substitutional nitrogen atom and an adjacent vacancy. This complex exhibits an optical transition with a fluorescence lifetime of 11.6 ns. The room temperature spectrum of the NV center consists of the zero-phonon line at 637 nm and broad phononic sidebands with a FWHM of more than 100 nm. Due to the existence of a shelving level the efficiency of the NV center as a single photon source is limited. Additionally, the high diffraction index of bulk diamond restricts the efficiency to collect the fluorescence light.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 1, 2009•4 citations

Optical depth localization of nitrogen-vacancy centers in diamond with nanometer accuracy

Andreas J. Häußler, Pascal Heller, Liam Paul McGuinness +2 more

Precise positioning of nitrogen-vacancy (NV) centers is crucial for their application in sensing and quantum information. Here we present a new purely optical technique enabling determination of the NV position with nanometer resolution. We use a confocal microscope to determine the position of individual emitters along the optical axis. Using two separate detection channels, it is possible to simultaneously measure reflected light from the diamond surface and fluorescent light from the NV center and statistically evaluate both signals. An accuracy of 2.6 nm for shallow NV centers was achieved and is consistent with other techniques for depth determination.

Optics Express•Nov 24, 2014•16 citations

Setup of a Confocal Fluorescence Microscope for the Detection and Characterization of Single NV Centers in Diamond

Manuel Riedmann, Lucas Kirchbach, Andreas Stute

Single nitrogen vacancy (NV) centers in diamond serve as a photonic platform for quantum sensing and computing applications. They can be created deterministically using femtosecond laser pulses. Such writing process requires high-resolution fluorescence detection with a high signal-to-noise ratio, which is accomplished by setting up a homebuilt confocal fluorescence microscope. The microscope shall monitor the fluorescence of newly formed NV centers during the writing process. In addition, it will be used to characterize the NV centers’ spin coherence times, orientation in the diamond lattice and single-emitter characteristics via the intensity correlation function g(2)(tau). In the future, this setup is also planned to be employed for STED-microscopy of twin NV centers.

•Feb 5, 2026•0 citations

Nanoscale Sensing Using Point Defects in Single-Crystal Diamond: Recent Progress on Nitrogen Vacancy Center-Based Sensors

Ettore Bernardi, Richard Nelz, Selda Sonusen +1 more

Individual, luminescent point defects in solids, so-called color centers, are atomic-sized quantum systems enabling sensing and imaging with nanoscale spatial resolution. In this overview, we introduce nanoscale sensing based on individual nitrogen vacancy (NV) centers in diamond. We discuss two central challenges of the field: first, the creation of highly-coherent, shallow NV centers less than 10 nm below the surface of a single-crystal diamond; second, the fabrication of tip-like photonic nanostructures that enable efficient fluorescence collection and can be used for scanning probe imaging based on color centers with nanoscale resolution.

arXiv:1704.04011•Crystals•Apr 28, 2017•64 citations

Optical and Spin Properties of NV Center Ensembles in Diamond Nano-Pillars

Kseniia Volkova, Julia Heupel, Sergei D. Trofimov +10 more

Nitrogen-vacancy (NV) color centers in diamond are excellent quantum sensors possessing high sensitivity and nano-scale spatial resolution. Their integration in photonic structures is often desired, since it leads to an increased photon emission and also allows the realization of solid-state quantum technology architectures. Here, we report the fabrication of diamond nano-pillars with diameters up to 1000 nm by electron beam lithography and inductively coupled plasma reactive ion etching in nitrogen-rich diamonds (type Ib) with [100] and [111] crystal orientations. The NV centers were created by keV-He ion bombardment and subsequent annealing, and we estimate an average number of NVs per pillar to be 4300 ± 300 and 520 ± 120 for the [100] and [111] samples, respectively. Lifetime measurements of the NVs’ excited state showed two time constants with average values of τ1 ≈ 2 ns and τ2 ≈ 8 ns, which are shorter as compared to a single color center in a bulk crystal (τ ≈ 10 ns). This is probably due to a coupling between the NVs as well as due to interaction with bombardment-induced defects and substitutional nitrogen (P1 centers). Optically detected magnetic resonance measurements revealed a contrast of about 5% and average coherence and relaxation times of T2 [100] = 420 ± 40 ns, T2 [111] = 560 ± 50 ns, and T1 [100] = 162 ± 11 μs, T1 [111] = 174 ± 24 μs. These pillars could find an application for scanning probe magnetic field imaging.

Nanomaterials•Apr 29, 2022•22 citations
The nitrogen-vacancy (NV) center is a defect in the structure of diamond, roughly the size of a single atom, that possesses properties that make it applicable to quantum information processing, high-resolution magnetic resonance imaging, and probing biological systems. When an NV center is excited by green light of wavelength 523 nm, it emits red light of in the range from 600-800 nm tens of nanoseconds later. A confocal microscope can be used to excite and collect emitted photons from NV centers. By detecting the intensity of the emitted red photons, we can determine the quantum state of a single NV center, which is needed to build various quantum computing, sensing and imaging devices. The autocorrelation method is used to detect antibunching in the emission of red photons and ascertain that the observed photons are being emitted from a single NV center. We have built an autocorrelation device that measures, with sub-nanosecond accuracy, the statistical distribution of the arrival times of the red photons emitted from a diamond sample at a photon counter. The device can measure fixed time values with a time resolution of 120 ps FWHM. For uncorrelated sources measured for 120 seconds at the TAC full range of 100 ns, the average counts in each histogram bin were about 0.01% of the predicted value. The autocorrelation device that we have built costs about 10 times less than commercial units used by other NV researchers.
For applications in Quantum Information and Quantum Key Distribution an on-demand source of single photons is desirable because absolute security is of utmost importance. Photons are quantum systems; hence encoding information onto them offers a secure alternative to classical cryptography as a measurement cannot be performed on photons without altering their properties. The Nitrogen Vacancy (NV) centre in diamond is a good source of such photons. It is photo-stable and its location in diamond offers robustness. It has zero phonon line at 637 nm and its relative short luminescence life-time of about 12 ns makes it suitable for generating single photons. This thesis covers two aspects: Firstly the characterization of defects in diamonds and subsequent selection of diamonds suitable for use in the single photon setup and secondly, the development of the experimental setup for single photon generation. This thesis sets out to describe the development of a laboratory based single photon source using the NV centre in diamond. For this purpose a suite of diamond samples were selected and subjected to various spectroscopic tests in order to characterize and classify the samples, especially the presence of the NV centres and their concentrations. The characterization of the defects was done through the use of the following spectroscopic techniques: UltravioletVisible-Near infrared spectroscopy, Infrared spectroscopy, Electron Spin Resonance and Photoluminescence. These techniques enabled us to understand the types and origins of crystal defects that were present in the diamond samples used in this study and to use this to select diamonds that are most suitable for use in generation of single photons. The experimental setup for single photon generation using the NV centre is based on a confocal microscope arrangement. Single NV centres were identified by measuring the second order autocorrelation function of the fluorescence light emitted by the sample when illuminated with a laser. This measurement was done using a Hanbury-Brown Twiss (HBT) interferometer.
The development of reliable devices to generate single photons is crucial for applications in quantum cryptography, as well as for fundamental quantum optics experiments. Due to their extremely high photostability at room temperature, optically active defects in solids, the so called color centers, are among the most promising candidates. Single NV (nitrogen-vacancy) centers in diamond have been demonstrated to be able to generate single photons and have already shown advantages compared to attenuated laser pulses in a quantum cryptography experiment. The nitrogen-vacancy center (NV center) in diamond consists of a substitutional nitrogen atom and an adjacent vacancy. This complex exhibits an optical transition with a fluorescence lifetime of 11.6 ns. The room temperature spectrum of the NV center consists of the zero-phonon line at 637 nm and broad phononic sidebands with a FWHM of more than 100 nm. Due to the existence of a shelving level the efficiency of the NV center as a single photon source is limited. Additionally, the high diffraction index of bulk diamond restricts the efficiency to collect the fluorescence light.
Precise positioning of nitrogen-vacancy (NV) centers is crucial for their application in sensing and quantum information. Here we present a new purely optical technique enabling determination of the NV position with nanometer resolution. We use a confocal microscope to determine the position of individual emitters along the optical axis. Using two separate detection channels, it is possible to simultaneously measure reflected light from the diamond surface and fluorescent light from the NV center and statistically evaluate both signals. An accuracy of 2.6 nm for shallow NV centers was achieved and is consistent with other techniques for depth determination.
Single nitrogen vacancy (NV) centers in diamond serve as a photonic platform for quantum sensing and computing applications. They can be created deterministically using femtosecond laser pulses. Such writing process requires high-resolution fluorescence detection with a high signal-to-noise ratio, which is accomplished by setting up a homebuilt confocal fluorescence microscope. The microscope shall monitor the fluorescence of newly formed NV centers during the writing process. In addition, it will be used to characterize the NV centers’ spin coherence times, orientation in the diamond lattice and single-emitter characteristics via the intensity correlation function g(2)(tau). In the future, this setup is also planned to be employed for STED-microscopy of twin NV centers.
Individual, luminescent point defects in solids, so-called color centers, are atomic-sized quantum systems enabling sensing and imaging with nanoscale spatial resolution. In this overview, we introduce nanoscale sensing based on individual nitrogen vacancy (NV) centers in diamond. We discuss two central challenges of the field: first, the creation of highly-coherent, shallow NV centers less than 10 nm below the surface of a single-crystal diamond; second, the fabrication of tip-like photonic nanostructures that enable efficient fluorescence collection and can be used for scanning probe imaging based on color centers with nanoscale resolution.
Nitrogen-vacancy (NV) color centers in diamond are excellent quantum sensors possessing high sensitivity and nano-scale spatial resolution. Their integration in photonic structures is often desired, since it leads to an increased photon emission and also allows the realization of solid-state quantum technology architectures. Here, we report the fabrication of diamond nano-pillars with diameters up to 1000 nm by electron beam lithography and inductively coupled plasma reactive ion etching in nitrogen-rich diamonds (type Ib) with [100] and [111] crystal orientations. The NV centers were created by keV-He ion bombardment and subsequent annealing, and we estimate an average number of NVs per pillar to be 4300 ± 300 and 520 ± 120 for the [100] and [111] samples, respectively. Lifetime measurements of the NVs’ excited state showed two time constants with average values of τ1 ≈ 2 ns and τ2 ≈ 8 ns, which are shorter as compared to a single color center in a bulk crystal (τ ≈ 10 ns). This is probably due to a coupling between the NVs as well as due to interaction with bombardment-induced defects and substitutional nitrogen (P1 centers). Optically detected magnetic resonance measurements revealed a contrast of about 5% and average coherence and relaxation times of T2 [100] = 420 ± 40 ns, T2 [111] = 560 ± 50 ns, and T1 [100] = 162 ± 11 μs, T1 [111] = 174 ± 24 μs. These pillars could find an application for scanning probe magnetic field imaging.