English
Related papers

Related papers: Efficient Pauli channel estimation with logarithmi…

200 papers

We consider the surface code under errors featuring both coherent and incoherent components and study the coherence of the corresponding logical noise channel and how this impacts information-theoretic measures of code performance, namely…

Quantum Physics · Physics 2025-12-03 Jan Behrends , Benjamin Béri

Fault-tolerant quantum computing will require accurate estimates of the resource overhead, but standard metrics such as gate fidelity and diamond distance have been shown to be poor predictors of logical performance. We present a scalable…

Quantum Physics · Physics 2023-01-26 Pavithran Iyer , Aditya Jain , Stephen D. Bartlett , Joseph Emerson

We consider protocols for estimating the parameter in a single-parameter unital qubit channel, assuming that the available initial states are highly mixed with very low purity. We compare two protocols, each invoking the channel once, via…

Quantum Physics · Physics 2026-04-14 David Collins , Taylor Larrechea

As quantum devices continue to grow in size but remain affected by noise, it is crucial to determine when and how they can outperform classical computers on practical tasks. A central piece in this effort is to develop the most efficient…

We prove an accuracy threshold theorem for fault-tolerant quantum computation based on error detection and postselection. Our proof provides a rigorous foundation for the scheme suggested by Knill, in which preparation circuits for ancilla…

Quantum Physics · Physics 2008-02-27 Panos Aliferis , Daniel Gottesman , John Preskill

Remarkable experimental advances in quantum computing are exemplified by recent announcements of impressive average gate fidelities exceeding 99.9% for single-qubit gates and 99% for two-qubit gates. Although these high numbers engender…

Quantum Physics · Physics 2015-12-29 Yuval R Sanders , Joel J Wallman , Barry C Sanders

Using near-term quantum computers to achieve a quantum advantage requires efficient strategies to improve the performance of the noisy quantum devices presently available. We develop and experimentally validate two efficient error…

Quantum error correction methods use processing power to combat noise. The noise level which can be tolerated in a fault-tolerant method is therefore a function of the computational resources available, especially the size of computer and…

Quantum Physics · Physics 2015-06-26 Andrew Steane

We propose a quantum error mitigation scheme for single-qubit measurement errors, particularly suited for one-way quantum computation. Contrary to well established error mitigation methods for circuit-based quantum computation, that require…

Quantum Physics · Physics 2024-11-15 Tobias Hartung , Stephan Schuster , Joachim von Zanthier , Karl Jansen

Pauli channels are widely used to describe errors in quantum computers, particularly when noise is shaped via Pauli twirling. A common assumption is that such channels admit a Markovian generator, namely a Pauli-Lindblad model with…

Quantum Physics · Physics 2026-03-20 Alireza Seif , Moein Malekakhlagh , Swarnadeep Majumder , Luke C. G. Govia

Twirling is a technique widely used for converting arbitrary noise channels into Pauli channels in error threshold estimations of quantum error correction codes. It is vitally useful both in real experiments and in classical quantum…

Quantum Physics · Physics 2019-11-04 Zhenyu Cai , Simon Benjamin

We present a [[7, 1, 3]] quantum error-correcting code that is able to achieve fault-tolerant syndrome measurement using one ancillary qubit per stabilizer for an error model of independent single-qubit Pauli errors. All single-qubit Pauli…

Quantum Physics · Physics 2017-10-04 Muyuan Li , Mauricio Gutiérrez , Stanley E. David , Alonzo Hernandez , Kenneth R. Brown

Quantum code surgery offers a flexible, low-overhead framework for executing logical measurements within quantum error-correcting codes. It encompasses several fault-tolerant logical computation schemes, including parallel surgery,…

Quantum Physics · Physics 2026-03-06 Andrew C. Yuan , Alexander Cowtan , Zhiyang He , Ting-Chun Lin , Dominic J. Williamson

The Heisenberg scaling is an ultimate precision limit of parameter estimation allowed by the principles of quantum mechanics, with no counterpart in the classical realm, and has been a long-pursued goal in quantum metrology. It has been…

Quantum Physics · Physics 2024-12-06 Jingyi Fan , Shengshi Pang

We propose a new quantum computing formalism named Pauli quantum computing. In this formalism, we use the Pauli basis $I$ and $X$ on the non-diagonal blocks of density matrices to encode information and treat them as the computational basis…

Quantum Physics · Physics 2024-12-05 Zhong-Xia Shang

Analogue quantum simulators offer a promising route to explore quantum many-body dynamics beyond classical reach in the near term. However, their vulnerability to noise limits the accuracy of simulations. Here, we establish a new framework…

Quantum Physics · Physics 2026-01-12 Gabriele Bressanini , Yue Ma , Hyukjoon Kwon , M. S. Kim

Estimating the expectation value of an operator corresponding to an observable is a fundamental task in quantum computation. It is often impossible to obtain such estimates directly, as the computer is restricted to measuring in a fixed…

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

Many quantum algorithms contain an important subroutine, the quantum amplitude estimation. As the name implies, this is essentially the parameter estimation problem and thus can be handled via the established statistical estimation theory.…

Quantum Physics · Physics 2022-01-10 Tomoki Tanaka , Shumpei Uno , Tamiya Onodera , Naoki Yamamoto , Yohichi Suzuki

We consider the problem of learning low-degree quantum objects up to $\varepsilon$-error in $\ell_2$-distance. We show the following results: $(i)$ unknown $n$-qubit degree-$d$ (in the Pauli basis) quantum channels and unitaries can be…