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Related papers: Optimal fast single pulse readout of qubits

200 papers

We describe how to perform fast quantum limited read-out of a solid state qubit biased at its degeneracy point. The method is based on homodyne detection of the phase of a microwave signal reflected by a slow oscillator coupled to the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 G. Johansson , L. Tornberg , C. M. Wilson

We present experimental results on a dispersive scheme for reading out a Josephson phase qubit. A capacitively shunted dc-SQUID is used as a nonlinear resonator which is inductively coupled to the qubit. We detect the flux state of the…

Superconductivity · Physics 2015-05-20 T. Wirth , J. Lisenfeld , A. Lukashenko , A. V. Ustinov

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…

Single-shot fidelity is the standard benchmark for superconducting qubit readout, yet it does not directly minimize the wall-clock time needed to certify a quantum state. We treat the dispersive measurement record as a stochastic…

Quantum Physics · Physics 2026-03-11 Sinan Bugu

Systematic errors in spin rotation operations using simple RF pulses place severe limitations on the usefulness of the pulsed magnetic resonance methods in quantum computing applications. In particular, the fidelity of quantum logic…

We employ pulse shaping to abate single-qubit gate errors arising from the weak anharmonicity of transmon superconducting qubits. By applying shaped pulses to both quadratures of rotation, a phase error induced by the presence of higher…

Mesoscale and Nanoscale Physics · Physics 2012-03-15 J. M. Chow , L. DiCarlo , J. M. Gambetta , F. Motzoi , L. Frunzio , S. M. Girvin , R. J. Schoelkopf

A classical computer simulating Schrodinger dynamics of a quantum system requires resources which scale exponentially with the size of the system, and is regarded as inefficient for such purposes. However, a quantum computer made up of a…

Quantum Physics · Physics 2015-06-16 Ravi Shankar , Swathi S. Hegde , T. S. Mahesh

We analyze a high-fidelity two-qubit gate using fast flux pulses on superconducting fluxonium qubits. The gate is realized by temporarily detuning magnetic flux through fluxonium loop away from the half flux quantum sweet spot. We simulate…

Quantum Physics · Physics 2022-09-28 Yinqi Chen , Konstantin N. Nesterov , Vladimir E. Manucharyan , Maxim G. Vavilov

Quantum simulation, the study of strongly correlated quantum matter using synthetic quantum systems, has been the most successful application of quantum computers to date. It often requires determining observables with high precision, for…

We report energy selective tunneling readout-based Hamiltonian parameter estimation of a two-electron spin qubit in a GaAs quantum dot array. Optimization of readout fidelity enables a single-shot measurement time of 16 on average, with…

We propose a experimentally feasible scheme to demonstrate the geometric phase in flux qubits by means of detuning coherent microwave pulse techniques. Through measuring the probability of the persistent current state in flux qubits, one…

Superconductivity · Physics 2007-05-23 Z. H. Peng , M. J. Zhang , D. N. Zheng

Quantum optimal control theory is applied to two and three coupled Josephson charge qubits. It is shown that by using shaped pulses a CNOT gate can be obtained with a trace fidelity > 0.99999 for the two qubits, and even when including…

The ability of pulse-shaping devices to generate accurately quantum optimal control is a strong limitation to the development of quantum technologies. We propose and demonstrate a systematic procedure to design robust digital control…

Quantum Physics · Physics 2022-10-18 Meri Harutyunyan , Frederic Holweck , Dominique Sugny , Stephane Guerin

Working with trapped atoms at close distance to each other, we show that one can implement entangling gates based on non-independent qubits using a single pulse per qubit, or a single structured pulse. The optimal parameters depend on…

Quantum Physics · Physics 2023-10-19 Ignacio R. Sola , Seokmin Shin , Bo Y. Chang

We present a numerically-optimized multipulse framework for the quantum control of a single-electron charge qubit. Our framework defines a set of pulse sequences, necessary for the manipulation of the ideal qubit basis, that avoids errors…

Quantum Physics · Physics 2023-03-10 Aleksander Lasek , Hugo V. Lepage , Kexin Zhang , Thierry Ferrus , Crispin H. W. Barnes

Three key metrics for readout systems in quantum processors are measurement speed, fidelity and footprint. Fast high-fidelity readout enables mid-circuit measurements, a necessary feature for many dynamic algorithms and quantum error…

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

Readout of superconducting qubits faces a trade-off between measurement speed and unwanted back-action on the qubit caused by the readout drive, such as $T_1$ degradation and leakage out of the computational subspace. The readout is…

Quantum Physics · Physics 2025-07-08 S. Hazra , W. Dai , T. Connolly , P. D. Kurilovich , Z. Wang , L. Frunzio , M. H. Devoret

We present a gradient-based method to construct high-fidelity, two-qubit quantum gates in a system consisting of two transmon qubits coupled via a tunable coupler. In particular, we focus on single flux quantum (SFQ) pulses as a promising…

Using a circuit QED device, we demonstrate a simple qubit measurement pulse shape that yields fast ring-up and ring-down of the readout resonator regardless of the qubit state. The pulse differs from a square pulse only by the inclusion of…

Quantum Physics · Physics 2016-02-03 D. T. McClure , Hanhee Paik , L. S. Bishop , M. Steffen , Jerry M. Chow , Jay M. Gambetta