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Related papers: Experimentally Realizable C-NOT Gate in a Flux Qub…

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We present a comprehensive analysis of quantum circuit fidelity across the full compilation stack, from high-level gate optimization through pulse-level control. Using a modular integration framework connecting a C++ circuit optimizer with…

Quantum Physics · Physics 2026-02-04 Rylan Malarchick

Noise is a hindering factor for current-era quantum computers. In this study, we experimentally validate the theoretical relationships between amplitude noise of the control signal and qubit state fidelity. The experiment comprises a 10x10…

We study the simulation of a single qubit rotation and Controlled-Not gate in a solid state one-dimensional chain of nuclear spins system interacting weakly through an Ising type of interaction with a modular component of the magnetic field…

Quantum Physics · Physics 2012-05-30 G. V. Lopez , M. Avila

Superconducting transmon qubits are a promising platform for quantum computation, yet they face significant fidelity degradation due to connectivity noise, particularly in the intermediate coupling regime where noise levels are substantial.…

Quantum Physics · Physics 2026-04-29 Quan Fu , Xin Wang , Rui Xiong

We present the study of a quantum Controlled-Controlled-Not gate, implemented in a chain of three nuclear spins weakly Ising interacting between all of them, that is, taking into account first and second neighbor spin interactions. This…

Quantum Physics · Physics 2009-11-13 Gustavo V. Lopez , Lorena Lara

We present a universal scheme of pulsed operations for the IBM oscillator-stabilized flux qubit comprising the CPHASE gate, single-qubit preparations and measurements. Based on numerical simulations, we argue that the error rates for these…

We present a scheme for implementing quantum operations with superconducting qubits. Our approach uses a "coupler" qubit to mediate a controllable, secular interaction between "data" qubits, pulse sequences which strongly mitigate the…

Quantum Physics · Physics 2013-10-22 Andrew J. Kerman , William D. Oliver

Recently, several groups have demonstrated two-qubit gate fidelities in semiconductor spin qubit systems above 99%. Achieving this regime of fault-tolerant compatible high fidelities is nontrivial and requires exquisite stability and…

We demonstrate a two-qubit logic gate driven by near-field microwaves in a room-temperature microfabricated ion trap. We measure a gate fidelity of 99.7(1)\%, which is above the minimum threshold required for fault-tolerant quantum…

Quantum Physics · Physics 2016-10-05 T. P. Harty , M. A. Sepiol , D. T. C. Allcock , C. J. Ballance , J. E. Tarlton , D. M. Lucas

Many realizations of solid-state qubits involve couplings to leakage states lying outside the computational subspace, posing a threat to high-fidelity quantum gate operations. Mitigating leakage errors is especially challenging when the…

Quantum Physics · Physics 2017-07-05 Joydip Ghosh , S. N. Coppersmith , Mark Friesen

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

Time-bin qubits, where information is encoded in a single photon at different times, have been widely used in optical fiber and waveguide based quantum communications. With the recent developments in distributed quantum computation, it is…

We present a systematic study of the phase-coherent dynamics of a superconducting three-Josephson-junction flux qubit. The qubit state is detected with the integrated-pulse method, which is a variant of the pulsed switching DC SQUID method.…

Superconductivity · Physics 2008-09-19 F. Deppe , M. Mariantoni , E. P. Menzel , S. Saito , K. Kakuyanagi , H. Tanaka , T. Meno , K. Semba , H. Takayanagi , R. Gross

Despite progress towards achieving low error rates with superconducting qubits, error-prone two-qubit gates remain a bottleneck for realizing large-scale quantum computers. Therefore, a systematic framework to design high-fidelity gates…

Several logical qubits and quantum gates have been proposed for semiconductor quantum dots controlled by voltages applied to top gates. The different schemes can be difficult to compare meaningfully. Here we develop a theoretical framework…

Mesoscale and Nanoscale Physics · Physics 2013-12-09 Teck Seng Koh , S. N. Coppersmith , Mark Friesen

A comparison of gate fidelities between different spin qubit types defined in quantum dots and a donor under different control errors is reported. We studied five qubit types, namely the quantum dot spin qubit, the double quantum dot…

Quantum Physics · Physics 2019-11-14 E. Ferraro , M. Fanciulli , M. De Michielis

Microwave trapped-ion quantum logic gates avoid spontaneous emission as a fundamental source of decoherence. However, microwave two-qubit gates are still slower than laser-induced gates and hence more sensitive to fluctuations and noise of…

Electron spins confined in quantum dots are an attractive system to realize high-fidelity qubits owing to their long coherence time. With the prolonged spin coherence time, however, the control fidelity can be limited by systematic errors…

Mesoscale and Nanoscale Physics · Physics 2018-10-30 K. Takeda , J. Yoneda , T. Otsuka , T. Nakajima , M. R. Delbecq , G. Allison , Y. Hoshi , N. Usami , K. M. Itoh , S. Oda , T. Kodera , S. Tarucha

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

The gate fidelity and the coherence time of a qubit are important benchmarks for quantum computation. We construct a qubit using a single electron spin in a Si/SiGe quantum dot and control it electrically via an artificial spin-orbit field…