English
Related papers

Related papers: Fidelity decay and error accumulation in random qu…

200 papers

We characterize the quantum gate fidelity in a state-independent manner by giving an explicit expression for its variance. The method we provide can be extended to calculate all higher order moments of the gate fidelity. Using these results…

Quantum Physics · Physics 2012-04-30 Easwar Magesan , Robin Blume-Kohout , Joseph Emerson

A major challenge in developing quantum computing technologies is to accomplish high precision tasks by utilizing multiplex optimization approaches, on both the physical system and algorithm levels. Loss functions assessing the overall…

Quantum Physics · Physics 2021-03-03 Zhen Wang , Yanzhu Chen , Zixuan Song , Dayue Qin , Hekang Li , Qiujiang Guo , H. Wang , Chao Song , Ying Li

The fidelity amplitude is a quantity of paramount importance in echo type experiments. We use semiclassical theory to study the average fidelity amplitude for quantum chaotic systems under external perturbation. We explain analytically two…

Chaotic Dynamics · Physics 2011-11-03 Ignacio García-Mata , Raúl O. Vallejos , Diego A. Wisniacki

It was shown in [T. Morimae, Phys. Rev. A {\bf81}, 060307(R) (2010)] that the gate fidelity of an inaccurate one-way quantum computation is upper bounded by a decreasing function of the amount of entanglement in the register. This means…

Quantum Physics · Physics 2015-05-20 Tomoyuki Morimae , Jonas Kahn

Designing encoding and decoding circuits to reliably send messages over many uses of a noisy channel is a central problem in communication theory. When studying the optimal transmission rates achievable with asymptotically vanishing error…

Quantum Physics · Physics 2024-11-07 Matthias Christandl , Alexander Müller-Hermes

The inevitable existence of static internal imperfections and residual interactions in some quantum computer architectures result in internal decoherence, dissipation, and destructive unitary shifts of active algorithms. By exact numerical…

Quantum Physics · Physics 2009-11-13 Murat Cetinbas , Joshua Wilkie

Encoding quantum information in a quantum error correction (QEC) code enhances protection against errors. Imperfection of quantum devices due to decoherence effects will limit the fidelity of quantum gate operations. In particular, neutral…

Quantum Physics · Physics 2026-03-03 J. J. Postema , S. J. J. M. F. Kokkelmans

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

The amplitude damping time, $T_1$, has long stood as the major factor limiting quantum fidelity in superconducting circuits, prompting concerted efforts in the material science and design of qubits aimed at increasing $T_1$. In contrast,…

Quantum Physics · Physics 2024-10-04 Aleksander Kubica , Arbel Haim , Yotam Vaknin , Fernando Brandão , Alex Retzker

Realistic fault-tolerant quantum computing at reasonable overhead requires two-qubit gates with the highest possible fidelity. Typically, an infidelity of $\lesssim 10^{-4}$ is recommended in the literature. Focusing on the phase-sensitive…

Quantum Physics · Physics 2023-11-28 Reinhold Blümel , Andrii Maksymov , Ming Li

Various quantum applications can be reduced to estimating expectation values, which are inevitably deviated by operational and environmental errors. Although errors can be tackled by quantum error correction, the overheads are far from…

Quantum Physics · Physics 2020-02-19 Shuaining Zhang , Yao Lu , Kuan Zhang , Wentao Chen , Ying Li , Jing-Ning Zhang , Kihwan Kim

The Eastin-Knill theorem is a central result of quantum error correction theory and states that a quantum code cannot correct errors exactly, possess continuous symmetries, and implement a universal set of gates transversely. As a way to…

Quantum Physics · Physics 2023-03-28 Guilherme Fiusa , Diogo O. Soares-Pinto , Diego Paiva Pires

Quantum computers require high fidelity quantum gates. These gates are obtained by routine calibration tasks that eat into the availability of cloud-based devices. Restless circuit execution speeds-up characterization and calibration by…

Quantum Physics · Physics 2023-11-10 Conrad J. Haupt , Daniel J. Egger

When modeling the effects of noise on quantum circuits, one often makes the assumption that these effects can be accounted for by individual decoherence events following an otherwise noise-free gate. In this work, we address the validity of…

Quantum Physics · Physics 2023-12-19 Keith R. Fratus , Juha Leppäkangas , Michael Marthaler , Jan-Michael Reiner

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…

It is important to study the behavior of a t-error correcting quantum code when the number of errors is greater than t, because it is likely that there are also small errors besides t large correctable errors. We give a lower bound for the…

Quantum Physics · Physics 2009-11-06 Ryutaroh Matsumoto

Quantum circuits implementing fault-tolerant quantum error correction (QEC) for the three qubit bit-flip code and five-qubit code are studied. To describe the effect of noise, we apply a model based on a generalized effective Hamiltonian…

Quantum Physics · Physics 2016-09-08 Y. C. Cheng , R. J. Silbey

We present a quantum circuit optimization technique that takes into account the variability in error rates that is inherent across present day noisy quantum computing platforms. This method can be run post qubit routing or post-compilation,…

Quantum Physics · Physics 2023-03-22 Paul D. Nation , Matthew Treinish

One of the largest obstacles to building a quantum computer is gate error, where the physical evolution of the state of a qubit or group of qubits during a gate operation does not match the intended unitary transformation. Gate error stems…

Quantum Physics · Physics 2018-02-07 Eliot Kapit

Understanding how errors deteriorate the information encoded in a many-body quantum system is a fundamental problem with practical implications for quantum technologies. Here, we investigate a class of encoding-decoding random circuits…

Quantum Physics · Physics 2025-01-22 Xhek Turkeshi , Piotr Sierant