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Related papers: Robust Two-Qubit Gates for Exchange-Coupled Qubits

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Quantum algorithms offer a dramatic speedup for computational problems in machine learning, material science, and chemistry. However, any near-term realizations of these algorithms will need to be heavily optimized to fit within the finite…

We show how to eliminate the first-order effects of the spin-orbit interaction in the performance of a two-qubit quantum gate. Our procedure involves tailoring the time dependence of the coupling between neighboring spins. We derive an…

Quantum Physics · Physics 2009-11-07 N. E. Bonesteel , D. Stepanenko , D. P. DiVincenzo

We propose a scheme with dc-control of finite bandwidth to implement two-qubit gate for superconducting flux qubits at the optimal point. We provide a detailed non-perturbative analysis on the dynamic evolution of the qubits interacting…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Y. D. Wang , A. Kemp , K. Semba

We propose a protocol for two-qubit quantum phase gate based upon reflection of photon pulses from a quantum dot in a cavity. Depending on the state of the quantum dot the reflected photons acquire a conditional phase shift. The key…

Quantum Physics · Physics 2012-12-20 Robert Johne , Andrea Fiore

Non-adiabatic two-qubit gate proposals for trapped-ion systems offer superior performance and flexibility over adiabatic schemes at the cost of increased laser control requirements. Existing fast gate schemes are limited by single-qubit…

We present two strategies for performing two-qubit operations on the electron spins of an exchange-coupled pair of phosphorus donors in silicon, using the ability to set the donor nuclear spins in arbitrary states. The effective magnetic…

Quantum Physics · Physics 2014-06-10 Rachpon Kalra , Arne Laucht , Charles Hill , Andrea Morello

Electron spins in semiconductors are promising qubits because their long coherence times enable nearly 10^9 coherent quantum gate operations. However, developing a scalable high-fidelity two-qubit gate remains challenging. Here, we…

Mesoscale and Nanoscale Physics · Physics 2016-08-16 John M. Nichol , Lucas A. Orona , Shannon P. Harvey , Saeed Fallahi , Geoffrey C. Gardner , Michael J. Manfra , Amir Yacoby

While quantum circuits are reaching impressive widths in the hundreds of qubits, their depths have not been able to keep pace. In particular, cloud computing gates on multi-qubit, fixed-frequency superconducting chips continue to hover…

Quantum Physics · Physics 2024-09-13 Boxi Li , Tommaso Calarco , Felix Motzoi

The three-qubit Toffoli gate plays an important role in quantum error correction and complex quantum algorithms such as Shor's factoring algorithm, motivating the search for efficient implementations of this gate. Here we introduce a…

Mesoscale and Nanoscale Physics · Physics 2019-08-15 M. J. Gullans , J. R. Petta

Charge qubits formed in double quantum dots represent quintessential two-level systems that enjoy both ease of control and efficient readout. Unfortunately, charge noise can cause rapid decoherence, with typical single-qubit gate fidelities…

Mesoscale and Nanoscale Physics · Physics 2019-03-11 Yuan-Chi Yang , S. N. Coppersmith , Mark Friesen

Two-qubit gates in trapped-ion quantum computers are generated by applying spin-dependent forces that temporarily entangle the internal state of the ion with its motion. Laser pulses are carefully designed to generate a maximally entangling…

Quantum Physics · Physics 2021-12-21 Mingyu Kang , Qiyao Liang , Bichen Zhang , Shilin Huang , Ye Wang , Chao Fang , Jungsang Kim , Kenneth R. Brown

In the model of gate-based quantum computation, the qubits are controlled by a sequence of quantum gates. In superconducting qubit systems, these gates can be implemented by voltage pulses. The success of implementing a particular gate can…

Quantum Physics · Physics 2017-12-04 D. Willsch , M. Nocon , F. Jin , H. De Raedt , K. Michielsen

We present a general procedure to implement a NOT gate by composite pulses robust against both offset uncertainties and control field variations. We define different degrees of robustness in this two-parameter space, namely along one, two…

Quantum Physics · Physics 2020-02-19 G. Dridi , M. Mejatty , S. J. Glaser , D. Sugny

We discuss the implementation of frequency selective rotations using sequences of hard pulses and delays. These rotations are suitable for implementing single qubit gates in Nuclear Magnetic Resonance (NMR) quantum computers, but can also…

Quantum Physics · Physics 2007-05-23 Mark D. Bowdrey , Jonathan A. Jones

Quantum computation holds the promise of solving computational problems which are believed to be classically intractable. However, in practice, quantum devices are still limited by their relatively short coherence times and imperfect…

Quantum Physics · Physics 2023-12-22 Sagar Silva Pratapsi , Diogo Cruz

Current efforts to build quantum computers focus mainly on the two-state qubit, which often involves suppressing readily-available higher states. In this work, we break this abstraction and synthesize short-duration control pulses for gates…

Robust qubit-qubit interactions mediated by bosonic modes are central to many quantum technologies. Existing proposals combining fast oscillator-mediated gates with dynamical decoupling require strong pulses or fast control over the…

Quantum Physics · Physics 2023-05-31 I. Arrazola , J. Casanova

We present a few-parameter ansatz for pulses to implement a broad set of simultaneous single-qubit rotations in frequency-crowded multilevel systems. Specifically, we consider a system of two qutrits whose working and leakage transitions…

Quantum Physics · Physics 2016-01-18 L. S. Theis , F. Motzoi , F. K. Wilhelm

We present a scheme to implement a universal set of quantum gates based on achievable interactions, and the gates can be protected against decoherences through dynamical-decoupling approach without encoding. By properly designing system…

Quantum Physics · Physics 2022-09-08 Chunfeng Wu , Chunfang Sun , Jing-Ling Chen , X. X. Yi

Because of their long coherence time and compatibility with industrial foundry processes, electron spin qubits are a promising platform for scalable quantum processors. A full-fledged quantum computer will need quantum error correction,…