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

arXiv:1002.1342 · Physical Review A

Quantum logical gates with four-level superconducting quantum interference devices coupled to a superconducting resonator

Xiao-Ling He, Chui‐Ping Yang, Li Sheng, JunYan Luo, Siyuan Han

Published Aug 4, 2010• 14 citations
arXivHTMLPDF

Abstract

We propose a way for realizing a two-qubit controlled phase gate with superconducting quantum interference devices (SQUIDs) coupled to a superconducting resonator. In this proposal, the two lowest levels of each SQUID serve as the logical states and two intermediate levels of each SQUID are used for the gate realization. We show that neither adjustment of SQUID level spacings during the gate operation nor uniformity in SQUID parameters is required by this proposal. In addition, this proposal does not require the adiabatic passage or a second-order detuning and thus the gate is much faster.

DOI
10.1103/physreva.82.024301

Related papers

n -qubit-controlled phase gate with superconducting quantum-interference devices coupled to a resonator

Chui‐Ping Yang, Siyuan Han

We present a way to realize an $n$-qubit controlled phase gate with superconducting quantum-interference devices (SQUIDs) by coupling them to a superconducting resonator. In this proposal, the two logical states of a qubit are represented by the two lowest levels of a SQUID. An intermediate level of each SQUID is utilized to facilitate coherent control and manipulation of quantum states of the qubits. It is interesting to note that an $n$-qubit controlled phase gate can be achieved with $n$ SQUIDs by successively applying a $\ensuremath{\pi}∕2$ Jaynes-Cummings pulse to each of the $n\ensuremath{-}1$ control SQUIDs before and after a $\ensuremath{\pi}$ Jaynes-Cummings pulse on the target SQUID.

arXiv:quant-ph/0504188•Physical Review A•Sep 9, 2005•92 citations

Quantum logic gates operation using SQUID qubits in bimodal cavity

Kehui Song

We present a scheme to realize the basic two-qubit logic gates such as the quantum phase gate and SWAP gate using a detuned microwave cavity interacting with three-level superconducting-quantum-interference-device (SQUID) qubit(s), by placing SQUID(s) in a two-mode microwave cavity and using adiabatic passage methods. In this scheme, the two logical states of the qubit are represented by the two lowest levels of the SQUID and the cavity fields are treated as quantized. Compared with the previous method, the complex procedures of adjusting the level spacing of the SQUID and applying the resonant microwave pulse to the SQUID to create transformation are not required. Based on superconducting device with relatively long decoherence time and simplified operation procedure, the gates operate at a high speed, which is important in view of decoherence.

Chinese Physics•Jan 16, 2006•17 citations

Realization of an n -qubit controlled- U gate with superconducting quantum interference devices or atoms in cavity QED

Chui‐Ping Yang, Siyuan Han

We propose an approach to realize an $n$-qubit controlled-$U$ gate with superconducting quantum interference devices (SQUIDs) in cavity QED. In this approach, the two lowest levels of a SQUID represent the two logical states of a qubit while a higher-energy intermediate level serves the gate manipulation. Our method operates essentially by creating a single photon through one of the control SQUIDs and then performing an arbitrary unitary transformation on the target SQUID with the assistance of the cavity photon. In addition, we show that the method can be applied to implement an $n$-qubit controlled-$U$ gate with atomic qubits in cavity QED.

arXiv:quant-ph/0511206•Physical Review A•Mar 15, 2006•86 citations

One-step implementation of a multiqubit controlled-phase gate with superconducting quantum interference devices coupled to a resonator

Y. Q. Zhang, Shou Zhang, Kyu Hwang Yeon +1 more

A scheme for one-step implementation of an n-qubit controlled-phase gate is proposed in a superconducting quantum interference device (SQUID) system. The distinguishing feature of this scheme is the simultaneous and nonidentical off-resonant Raman coupling of the n SQUID qubits to a single-mode resonator and the microwave pulses. The scheme is efficient and simple because it requires only one-step evolution, and no adjustments of the experimental parameters are needed during the operation.

Journal of the Optical Society of America B•Feb 10, 2012•6 citations

An Efficient Scheme for Implementing an N -Qubit Toffoli Gate with Superconducting Quantum-Interference Devices in Cavity QED

Anshou Zheng, Ji-Bing Liu, Xiang Dong +2 more

An alternative approach is proposed to realize an n -qubit Toffoli gate with superconducting quantum-interference devices (SQUIDs) in cavity quantum electrodynamics (QED). In the proposal, we represent two logical gates of a qubit with the two lowest levels of a SQUID while a higher-energy intermediate level of each SQUID is utilized for the gate manipulation. During the operating process, because the cavity field is always in vacuum state, the requirement on the cavity is greatly loosened and there is no transfer of quantum information between the cavity and SQUIDs.

Chinese Physics Letters•Aug 23, 2007•3 citations

Rotation gate for a three-level superconducting quantum interference device qubit with resonant interaction

Chui‐Ping Yang, Siyuan Han

We show a way to realize an arbitrary rotation gate in a three-level superconducting quantum interference device (SQUID) qubit using resonant interaction. In this approach, the two logical states of the qubit are represented by the two lowest levels of the SQUID and a higher-energy intermediate level is utilized for the gate manipulation. By considering spontaneous decay from the intermediate level during the gate operation, we present a formula for calculating average fidelity over all possible initial states. Finally, based on realistic system parameters, we show that an arbitrary rotation gate can be achieved with a high fidelity in a SQUID.

Physical Review A•Oct 9, 2006•29 citations
We propose a way for realizing a two-qubit controlled phase gate with superconducting quantum interference devices (SQUIDs) coupled to a superconducting resonator. In this proposal, the two lowest levels of each SQUID serve as the logical states and two intermediate levels of each SQUID are used for the gate realization. We show that neither adjustment of SQUID level spacings during the gate operation nor uniformity in SQUID parameters is required by this proposal. In addition, this proposal does not require the adiabatic passage or a second-order detuning and thus the gate is much faster.
We present a way to realize an nnn-qubit controlled phase gate with superconducting quantum-interference devices (SQUIDs) by coupling them to a superconducting resonator. In this proposal, the two logical states of a qubit are represented by the two lowest levels of a SQUID. An intermediate level of each SQUID is utilized to facilitate coherent control and manipulation of quantum states of the qubits. It is interesting to note that an nnn-qubit controlled phase gate can be achieved with nnn SQUIDs by successively applying a $\ensuremath{\pi}∕2$ Jaynes-Cummings pulse to each of the $n\ensuremath{-}1$ control SQUIDs before and after a $\ensuremath{\pi}$ Jaynes-Cummings pulse on the target SQUID.
We present a scheme to realize the basic two-qubit logic gates such as the quantum phase gate and SWAP gate using a detuned microwave cavity interacting with three-level superconducting-quantum-interference-device (SQUID) qubit(s), by placing SQUID(s) in a two-mode microwave cavity and using adiabatic passage methods. In this scheme, the two logical states of the qubit are represented by the two lowest levels of the SQUID and the cavity fields are treated as quantized. Compared with the previous method, the complex procedures of adjusting the level spacing of the SQUID and applying the resonant microwave pulse to the SQUID to create transformation are not required. Based on superconducting device with relatively long decoherence time and simplified operation procedure, the gates operate at a high speed, which is important in view of decoherence.
We propose an approach to realize an nnn-qubit controlled-UUU gate with superconducting quantum interference devices (SQUIDs) in cavity QED. In this approach, the two lowest levels of a SQUID represent the two logical states of a qubit while a higher-energy intermediate level serves the gate manipulation. Our method operates essentially by creating a single photon through one of the control SQUIDs and then performing an arbitrary unitary transformation on the target SQUID with the assistance of the cavity photon. In addition, we show that the method can be applied to implement an nnn-qubit controlled-UUU gate with atomic qubits in cavity QED.
An alternative approach is proposed to realize an n -qubit Toffoli gate with superconducting quantum-interference devices (SQUIDs) in cavity quantum electrodynamics (QED). In the proposal, we represent two logical gates of a qubit with the two lowest levels of a SQUID while a higher-energy intermediate level of each SQUID is utilized for the gate manipulation. During the operating process, because the cavity field is always in vacuum state, the requirement on the cavity is greatly loosened and there is no transfer of quantum information between the cavity and SQUIDs.
We show a way to realize an arbitrary rotation gate in a three-level superconducting quantum interference device (SQUID) qubit using resonant interaction. In this approach, the two logical states of the qubit are represented by the two lowest levels of the SQUID and a higher-energy intermediate level is utilized for the gate manipulation. By considering spontaneous decay from the intermediate level during the gate operation, we present a formula for calculating average fidelity over all possible initial states. Finally, based on realistic system parameters, we show that an arbitrary rotation gate can be achieved with a high fidelity in a SQUID.