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Related papers: Charge sensitivity in the transmon regime

200 papers

Superconducting qubits are one of the most promising physical systems for implementing quantum computers. However, executing quantum algorithms of practical computational advantage requires further improvements in the fidelities of qubit…

A quantum computer that can be constructed based on a superconducting nanocircuits has previously been proposed. We examine the effect of background charge fluctuations on a coupled Josephson charge qubit system used in such a computer. In…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Toshifumi Itakura , Yasuhiro Tokura

We benchmark the decoherence of superconducting qubits to examine the temporal stability of energy-relaxation and dephasing. By collecting statistics during measurements spanning multiple days, we find the mean parameters $\overline{T_{1}}$…

Transmon qubits experience open system effects that manifest as noise at a broad range of frequencies. We present a model of these effects using the Redfield master equation with a hybrid bath consisting of low and high-frequency…

Quantum Physics · Physics 2024-08-15 Vinay Tripathi , Huo Chen , Eli Levenson-Falk , Daniel A. Lidar

In this work, we revisit the idea of using an interferometer of pairs of Josephson junctions as a protected rhombus qubit. Unlike in the original proposal, where the qubit states are encoded into odd and even parity charge states, here, we…

We report on spectroscopic and time-domain measurements on a fixed-frequency concentric transmon qubit in an applied in-plane magnetic field to explore its limits of magnetic field compatibility. We demonstrate quantum coherence of the…

Many quantum dot qubits operate in regimes where the energy splittings between qubit states are large and phonons can be the dominant source of decoherence. The recently proposed charge quadrupole qubit, based on one electron in a triple…

Mesoscale and Nanoscale Physics · Physics 2018-11-05 Viktoriia Kornich , Maxim G. Vavilov , Mark Friesen , S. N. Coppersmith

It has been proposed that a quantum computer can be constructed based on electron spins in quantum dots or based on a superconducting nanocircuit. During two-qubit operations, the fluctuation of the coupling parameters is a critical factor.…

Materials Science · Physics 2009-11-10 Toshifumi Itakura

Spin qubits in Silicon quantum dots can have long coherence times, yet their manipulation relies on the exchange interaction, through which charge noise can induce decoherence. Charge traps near the interface of a Si heterostructure lead to…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Dimitrie Culcer , Xuedong Hu , S. Das Sarma

Transmon qubits are ubiquitously used in superconducting quantum information processor architectures. Strong drives are required to realize fast, high-fidelity, gates and measurements, including parametrically activated processes. Here, we…

Quantum Physics · Physics 2022-11-11 Joachim Cohen , Alexandru Petrescu , Ross Shillito , Alexandre Blais

Pure dephasing is the dominant leak mechanism in photonic cat qubits because its phase errors disrupt the parity protection, rendering the qubit vulnerable to energy relaxation. In this manuscript, we reveal that this dephasing mechanism…

Quantum Physics · Physics 2025-11-07 Ke-Xiong Yan , Zhi-Cheng Shi , Ye-Hong Chen , Yan Xia

Spin qubits in semiconductor quantum dots are one of the promizing devices to realize a quantum processor. A better knowledge of the noise sources affecting the coherence of such a qubit is therefore of prime importance. In this work, we…

Mesoscale and Nanoscale Physics · Physics 2023-04-04 Baker Shalak , Christophe Delerue , Yann-Michel Niquet

In this study, we examine decoherence of qubits system coupled independently by using influence functional. We especially concentrated on the effect of qubit flip process. We examine the zero-dimensional qubit and one-dimensional qubits…

Quantum Physics · Physics 2008-09-30 Toshifumi Itakura

We demonstrate improved operation of exchange-coupled semiconductor quantum dots by substantially reducing the sensitivity of exchange operations to charge noise. The method involves biasing a double-dot symmetrically between the…

Ramsey oscillations typically exhibit an exponential decay envelope due to environmental noise. However, recent experiments have observed nonmonotonic Ramsey fringes characterized by beating patterns, which deviate from the standard…

The rate of charge-parity switching in a full-shell superconductor-semiconductor nanowire qubit is measured by directly monitoring the dispersive shift of a readout resonator. At zero magnetic field, the measured switching time scale $T_P$…

Mesoscale and Nanoscale Physics · Physics 2023-10-03 O. Erlandsson , D. Sabonis , A. Kringhøj , T. W. Larsen , P. Krogstrup , K. D. Petersson , C. M. Marcus

We report a direct measurement of the low-frequency noise spectrum in a superconducting flux qubit. Our method uses the noise sensitivity of a free-induction Ramsey interference experiment, comprising free evolution in the presence of noise…

Electron spins in silicon quantum dots are excellent qubits due to their long coherence times, scalability, and compatibility with advanced semiconductor technology. Although high gate fidelities can be achieved with spin qubits, charge…

Mesoscale and Nanoscale Physics · Physics 2024-12-13 Feiyang Ye , Ammar Ellaboudy , Dylan Albrecht , Rohith Vudatha , N. Tobias Jacobson , John M. Nichol

In the past two decades, one of the fascinating subjects in quantum physics has been quantum bits (qubits). Thanks to the superposition principle, the qubits can perform many calculations simultaneously, which will significantly increase…

Quantum Physics · Physics 2023-09-12 H. Zarrabi , S. Hajihosseini , M. Fardmanesh , S. I. Mirzaei

Noise is a major challenge in quantum computing, affecting the reliability of quantum protocols. In this work, we analytically study the impact of various noise processes, such as depolarization, bit flip, and phase flip, on the quantum…

Quantum Physics · Physics 2026-04-10 Imama Tul Birrah Khan , Muhammad Faryad