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

Quantum Information Processing

Quantum controlled-not gate in the bad cavity regime

Zhao-Hui Peng, Le‐Man Kuang, Jian Zou, Yuqing Zhang, Xiaojuan Liu

Published May 13, 2015• 8 citations
Publisher
DOI
10.1007/s11128-015-1017-x

Related papers

Universal quantum gates for photon-atom hybrid systems assisted by bad cavities

Guan-Yu Wang, Qian Liu, Hai‐Rui Wei +3 more

We present two deterministic schemes for constructing a CNOT gate and a Toffoli gate on photon-atom and photon-atom-atom hybrid quantum systems assisted by bad cavities, respectively. They are achieved by cavity-assisted photon scattering and work in the intermediate coupling region with bad cavities, which relaxes the difficulty of their implementation in experiment. Also, bad cavities are feasible for fast quantum operations and reading out information. Compared with previous works, our schemes do not need any auxiliary qubits and measurements. Moreover, the schematic setups for these gates are simple, especially that for our Toffoli gate as only a quarter wave packet is used to interact the photon with each of the atoms every time. These atom-cavity systems can be used as the quantum nodes in long-distance quantum communication as their relatively long coherence time is suitable for multi-time operations between the photon and the system. Our calculations show that the average fidelities and efficiencies of our two universal hybrid quantum gates are high with current experimental technology.

arXiv:1509.00293•Scientific Reports•Apr 12, 2016•16 citations

An all-optical quantum controlled-NOT gate

Jeremy L. O’Brien, Geoff J. Pryde, AG White +2 more

•Dec 1, 2003•2 citations

Realization of quantum controlled-NOT gate with resonant interaction

Zhiming Zhan

Physica A Statistical Mechanics and its Applications•Jul 23, 2007•2 citations

Universal hyperparallel hybrid photonic quantum gates with dipole-induced transparency in the weak-coupling regime

Bao‐Cang Ren, Guanyu Wang, Fu‐Guo Deng

We present the dipole induced transparency (DIT) of a diamond nitrogen-vacancy center embedded in a photonic crystal cavity coupled to two waveguides, and it is obvious with the robust and flexible reflectance and transmittance difference of circularly polarized lights between the uncoupled and the coupled cavities even in the bad cavity regime (the Purcell regime). With this DIT, we propose two universal hyperparallel hybrid photonic quantum logic gates, including a hybrid hyper-controlled-not gate and a hybrid hyper-Toffoli gate, on photon systems in both the polarization and the spatial-mode degrees of freedom (DOFs), which are equal to two identical quantum logic gates operating simultaneously on the systems in one DOF. They can be used to perform more quantum operations with less resources in the quantum information protocols with multiqubit systems in several DOFs, which may depress the resources consumed and the photonic dissipation. Moreover, they are more robust against asymmetric environment noise in the weak-coupling regime, compared with the integration of two cascaded quantum logic gates in one DOF.

arXiv:1411.0274•Physical Review A•Mar 30, 2015•126 citations

An Introduction to All-Optical Quantum Controlled-NOT Gates

Hongjuan He, Junjie Wu, Xuan Zhu

Communications in computer and information science•Jan 1, 2016•4 citations

Tunable cavity coupling of a single Sn - V − center in nanodiamond across the bad-emitter and bad-cavity regimes

Selene Sachero, Robert Berghaus, Florian Feuchtmayr +5 more

Efficient coupling between quantum emitters and optical cavities is essential for scalable quantum photonic technologies. Group-IV vacancy centers in diamond, particularly the negatively charged tin-vacancy center, have emerged as promising candidates due to their spectral stability, high Debye-Waller factor, and large orbital splitting in ground states. Here, we demonstrate controlled coupling of a single negatively charged tin-vacancy center hosted in a nanodiamond to a fully tunable Fabry-Pérot microcavity. At cryogenic temperatures, we access the weak-coupling regime and observe a transition from the bad-emitter regime to the bad-cavity regime as the optical transition of the color center narrows. At 4 K, a Purcell factor exceeding 1.7 is measured, confirming cavity-enhanced emission. The obtained results demonstrate the potential of Sn − V − centers in nanodiamonds as a coherent single-photon source for quantum networks.

arXiv:2507.06553•Physical Review Applied•Nov 20, 2025•0 citations
We present two deterministic schemes for constructing a CNOT gate and a Toffoli gate on photon-atom and photon-atom-atom hybrid quantum systems assisted by bad cavities, respectively. They are achieved by cavity-assisted photon scattering and work in the intermediate coupling region with bad cavities, which relaxes the difficulty of their implementation in experiment. Also, bad cavities are feasible for fast quantum operations and reading out information. Compared with previous works, our schemes do not need any auxiliary qubits and measurements. Moreover, the schematic setups for these gates are simple, especially that for our Toffoli gate as only a quarter wave packet is used to interact the photon with each of the atoms every time. These atom-cavity systems can be used as the quantum nodes in long-distance quantum communication as their relatively long coherence time is suitable for multi-time operations between the photon and the system. Our calculations show that the average fidelities and efficiencies of our two universal hybrid quantum gates are high with current experimental technology.
We present the dipole induced transparency (DIT) of a diamond nitrogen-vacancy center embedded in a photonic crystal cavity coupled to two waveguides, and it is obvious with the robust and flexible reflectance and transmittance difference of circularly polarized lights between the uncoupled and the coupled cavities even in the bad cavity regime (the Purcell regime). With this DIT, we propose two universal hyperparallel hybrid photonic quantum logic gates, including a hybrid hyper-controlled-not gate and a hybrid hyper-Toffoli gate, on photon systems in both the polarization and the spatial-mode degrees of freedom (DOFs), which are equal to two identical quantum logic gates operating simultaneously on the systems in one DOF. They can be used to perform more quantum operations with less resources in the quantum information protocols with multiqubit systems in several DOFs, which may depress the resources consumed and the photonic dissipation. Moreover, they are more robust against asymmetric environment noise in the weak-coupling regime, compared with the integration of two cascaded quantum logic gates in one DOF.
Efficient coupling between quantum emitters and optical cavities is essential for scalable quantum photonic technologies. Group-IV vacancy centers in diamond, particularly the negatively charged tin-vacancy center, have emerged as promising candidates due to their spectral stability, high Debye-Waller factor, and large orbital splitting in ground states. Here, we demonstrate controlled coupling of a single negatively charged tin-vacancy center hosted in a nanodiamond to a fully tunable Fabry-Pérot microcavity. At cryogenic temperatures, we access the weak-coupling regime and observe a transition from the bad-emitter regime to the bad-cavity regime as the optical transition of the color center narrows. At 4 K, a Purcell factor exceeding 1.7 is measured, confirming cavity-enhanced emission. The obtained results demonstrate the potential of Sn − V − centers in nanodiamonds as a coherent single-photon source for quantum networks.