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

Optics and Spectroscopy

Creation of entangled state between two spaced NV centers in diamond

Alexander A. Bukach, S. Ya. Kilin

Published Feb 1, 2010• 3 citations
Publisher

Abstract

A method for creating an entangled state between two NV centers in a diamond that do not interact directly with each other is studied. The method is based on the excitation of centers via a half divider (a 50% beamsplitter) with the subsequent coherent inversion of the spin of the excited center and the detection of a photon emitted by the excited center. The parameters of a multimode single-photon pulse that make it possible to achieve a maximally possible excitation of the centers at a given solid angle of the focusing of the light on the center are found. The probability to create an entangled state in relation to the parameters of the initial state of a photon, the turn-on and turn-off times of the microwave pulse and the light focusing solid angle is determined. Optimal values of these parameters that ensure a maximal probability of the entanglement creation are determined.

DOI
10.1134/s0030400x10020153

Related papers

Creation of an entangled state between two NV centers in a single-photon interferometric scheme

Alexander A. Bukach, S. Ya. Kilin

We study a method for creating an entangled state between two NV centers in diamond that do not directly interact with each other. The method is based on excitation of centers with a single photon via a half divider with subsequent coherent inversion of the spin of the excited center by a microwave pulse and on the detection of a photon that was emitted by the excited center and that passed through the divider. We consider the general case in which the transition frequencies of the centers are shifted with respect to each other and the control pulses are detuned with respect to these transitions. We find the probability of creating an entangled state and its fidelity in relation to the parameters of the method and transition frequencies of the centers. Optimal values of these parameters are determined.

Optics and Spectroscopy•Oct 1, 2011•0 citations

Quantum Optics with Atom-like Systems in Diamond

Yiwen Chu

The nitrogen vacancy (NV) center in diamond is a unique quantum system that combines solid state spin qubits with coherent optical transitions. The spin states of the NV center can be initialized, read out, and controlled with RF fields at room temperature. It can be coupled to other spin systems in the environment while at the same time maintaining an extraordinary degree of quantum coherence. Experiments utilizing the NV center's spin states have led to a wide range of demonstrations from quantum error correction to high-sensitivity magnetometry. This thesis, however, focuses on creating an interface between NV centers and light in the visible domain by making use of its optical transitions. Such an interface connects the quantum system consisting of NV centers and nuclear spins to photons, which can then be used to both manipulate the spin qubits themselves or transport quantum information over large distances.

•Jun 6, 2014•1 citation

Quantum Control of Single Spins and Photons in Diamond: Towards Solid-state Implementation of Quantum Repeaters

Lily Childress

The complex environment of solid-state quantum bits is generally believed to pose a difficult challenge for solid state realizations of quantum information science. Close study of single electronic spins associated with the nitrogen-vacancy (NV) center in diamond has shown how a complex environment -- in this case a spin-bath formed by carbon-13 isotopic impurities -- may be understood and even controlled. Specifically, we show that optical and microwave excitation of the NV center can be used to perform robust initialization, manipulation, and measurement of the two-qubit register formed by the electronic spin and its nearest-neighbor carbon-13 nuclear spin. These few-qubit registers may be used as a basis for scalable quantum information systems provided that one can identify a means to connect different registers. For an optically active system such as the NV center, photons provide a natural medium for inter- register communication, and we discuss initial experiments studying the possibility of quantum optical interconnects. Such an optically-connected few-qubit register offers a flexible hardware for both quantum computation and long-distance quantum communication; in particular, it may allow realization of a solid-state quantum repeater.

Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR)•Aug 1, 2007•1 citation

Entangling remote qubits using the single-photon protocol: an in-depth theoretical and experimental study

Sophie Hermans, Matteo Pompili, Laura dos Santos Martins +5 more

Abstract The generation of entanglement between remote matter qubits has developed into a key capability for fundamental investigations as well as for emerging quantum technologies. In the single-photon, protocol entanglement is heralded by generation of qubit-photon entangled states and subsequent detection of a single photon behind a beam splitter. In this work we perform a detailed theoretical and experimental investigation of this protocol and its various sources of infidelity. We develop an extensive theoretical model and subsequently tailor it to our experimental setting, based on nitrogen-vacancy centers in diamond. Experimentally, we verify the model by generating remote states for varying phase and amplitudes of the initial qubit superposition states and varying optical phase difference of the photons arriving at the beam splitter. We show that a static frequency offset between the optical transitions of the qubits leads to an entangled state phase that depends on the photon detection time. We find that the implementation of a Charge-Resonance check on the nitrogen-vacancy center yields transform-limited linewidths. Moreover, we measure the probability of double optical excitation, a significant source of infidelity, as a function of the power of the excitation pulse. Finally, we find that imperfect optical excitation can lead to a detection-arm-dependent entangled state fidelity and rate. The conclusion presented here are not specific to the nitrogen-vacancy centers used to carry out the experiments, and are therefore readily applicable to other qubit platforms.

arXiv:2208.07449•New Journal of Physics•Jan 1, 2023•45 citations

Spin coherence mapping of NV centers in diamond

Lucas Nunes Sales de Andrade, Charlie Oncebay Segura, Sérgio Ricardo Muniz

In recent years, nitrogen-vacancy (NV) color centers in diamond have become excellent solid-state quantum sensors due to their electronic spin properties. Especially for their easy optical initialization and detection, together with their very large spin coherence at room temperature. Many studies have reported their use for sensing temperature, strain, electric fields, and mainly magnetic fields. Here, we show how to build a two-dimensional map of the electronic spin coherence of an ensemble of NV centers in ultra-pure diamond, using an optical imaging protocol combined with microwave pulses relying simply on a regular CCD camera.

arXiv:2209.05577•Sep 12, 2022•0 citations

A quantum computer based on NV centers in diamond: Optically detected nutations of single electron and nuclear spins

Alexander P. Nizovtsev, S. Ya. Kilin, Fedor Jelezko +4 more

In an effort to realize a two-bit processor for a quantum computer on the basis of single nitrogen-vacancy defect centers (NV centers) in diamond, the optically detected nutations of the electron spin of a single NV center in the ground state and of the nuclear spin of a 13 C atom located at a diamond lattice site nearest to the NV center are studied. The photodynamics of NV and NV + 13 C centers under different temperatures and optical excitation conditions is discussed. A seven-level model of a center excited by radiation from an Ar + laser at room temperature is proposed. On the basis of this model, the experimental spectra of optically detected electron paramagnetic and electron-nuclear double resonances of single NV and NV + 13 C centers in diamond nanocrystals, as well as experimental data on the optically detected nutations of the electron and nuclear spins of these centers caused by the actions of pulsed microwave and radiofrequency fields, respectively, are interpreted.

Optics and Spectroscopy•Aug 1, 2005•75 citations
A method for creating an entangled state between two NV centers in a diamond that do not interact directly with each other is studied. The method is based on the excitation of centers via a half divider (a 50% beamsplitter) with the subsequent coherent inversion of the spin of the excited center and the detection of a photon emitted by the excited center. The parameters of a multimode single-photon pulse that make it possible to achieve a maximally possible excitation of the centers at a given solid angle of the focusing of the light on the center are found. The probability to create an entangled state in relation to the parameters of the initial state of a photon, the turn-on and turn-off times of the microwave pulse and the light focusing solid angle is determined. Optimal values of these parameters that ensure a maximal probability of the entanglement creation are determined.
We study a method for creating an entangled state between two NV centers in diamond that do not directly interact with each other. The method is based on excitation of centers with a single photon via a half divider with subsequent coherent inversion of the spin of the excited center by a microwave pulse and on the detection of a photon that was emitted by the excited center and that passed through the divider. We consider the general case in which the transition frequencies of the centers are shifted with respect to each other and the control pulses are detuned with respect to these transitions. We find the probability of creating an entangled state and its fidelity in relation to the parameters of the method and transition frequencies of the centers. Optimal values of these parameters are determined.
The nitrogen vacancy (NV) center in diamond is a unique quantum system that combines solid state spin qubits with coherent optical transitions. The spin states of the NV center can be initialized, read out, and controlled with RF fields at room temperature. It can be coupled to other spin systems in the environment while at the same time maintaining an extraordinary degree of quantum coherence. Experiments utilizing the NV center's spin states have led to a wide range of demonstrations from quantum error correction to high-sensitivity magnetometry. This thesis, however, focuses on creating an interface between NV centers and light in the visible domain by making use of its optical transitions. Such an interface connects the quantum system consisting of NV centers and nuclear spins to photons, which can then be used to both manipulate the spin qubits themselves or transport quantum information over large distances.
The complex environment of solid-state quantum bits is generally believed to pose a difficult challenge for solid state realizations of quantum information science. Close study of single electronic spins associated with the nitrogen-vacancy (NV) center in diamond has shown how a complex environment -- in this case a spin-bath formed by carbon-13 isotopic impurities -- may be understood and even controlled. Specifically, we show that optical and microwave excitation of the NV center can be used to perform robust initialization, manipulation, and measurement of the two-qubit register formed by the electronic spin and its nearest-neighbor carbon-13 nuclear spin. These few-qubit registers may be used as a basis for scalable quantum information systems provided that one can identify a means to connect different registers. For an optically active system such as the NV center, photons provide a natural medium for inter- register communication, and we discuss initial experiments studying the possibility of quantum optical interconnects. Such an optically-connected few-qubit register offers a flexible hardware for both quantum computation and long-distance quantum communication; in particular, it may allow realization of a solid-state quantum repeater.
Abstract The generation of entanglement between remote matter qubits has developed into a key capability for fundamental investigations as well as for emerging quantum technologies. In the single-photon, protocol entanglement is heralded by generation of qubit-photon entangled states and subsequent detection of a single photon behind a beam splitter. In this work we perform a detailed theoretical and experimental investigation of this protocol and its various sources of infidelity. We develop an extensive theoretical model and subsequently tailor it to our experimental setting, based on nitrogen-vacancy centers in diamond. Experimentally, we verify the model by generating remote states for varying phase and amplitudes of the initial qubit superposition states and varying optical phase difference of the photons arriving at the beam splitter. We show that a static frequency offset between the optical transitions of the qubits leads to an entangled state phase that depends on the photon detection time. We find that the implementation of a Charge-Resonance check on the nitrogen-vacancy center yields transform-limited linewidths. Moreover, we measure the probability of double optical excitation, a significant source of infidelity, as a function of the power of the excitation pulse. Finally, we find that imperfect optical excitation can lead to a detection-arm-dependent entangled state fidelity and rate. The conclusion presented here are not specific to the nitrogen-vacancy centers used to carry out the experiments, and are therefore readily applicable to other qubit platforms.
In recent years, nitrogen-vacancy (NV) color centers in diamond have become excellent solid-state quantum sensors due to their electronic spin properties. Especially for their easy optical initialization and detection, together with their very large spin coherence at room temperature. Many studies have reported their use for sensing temperature, strain, electric fields, and mainly magnetic fields. Here, we show how to build a two-dimensional map of the electronic spin coherence of an ensemble of NV centers in ultra-pure diamond, using an optical imaging protocol combined with microwave pulses relying simply on a regular CCD camera.
In an effort to realize a two-bit processor for a quantum computer on the basis of single nitrogen-vacancy defect centers (NV centers) in diamond, the optically detected nutations of the electron spin of a single NV center in the ground state and of the nuclear spin of a 13 C atom located at a diamond lattice site nearest to the NV center are studied. The photodynamics of NV and NV + 13 C centers under different temperatures and optical excitation conditions is discussed. A seven-level model of a center excited by radiation from an Ar + laser at room temperature is proposed. On the basis of this model, the experimental spectra of optically detected electron paramagnetic and electron-nuclear double resonances of single NV and NV + 13 C centers in diamond nanocrystals, as well as experimental data on the optically detected nutations of the electron and nuclear spins of these centers caused by the actions of pulsed microwave and radiofrequency fields, respectively, are interpreted.