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Related papers: Note on the Margolus-Levitin quantum speed limit f…

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Quantum speed limit (QSL) defines the theoretical upper bound on how fast a quantum system can evolve between states. It imposes a fundamental constraint on the rate of quantum information processing. For a relativistic spin-up electron in…

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

Leveraging quantum information geometry, we derive generalized quantum speed limits on the rate of change of the expectation values of observables. These bounds subsume and, for Hilbert space dimension $\geq 3$, tighten existing bounds --…

Recently, some quantum algorithms have been implemented by quantum adiabatic evolutions. In this paper, we discuss the accurate relation between the running time and the distance of the initial state and the final state of a kind of quantum…

Quantum Physics · Physics 2009-11-11 Zhaohui Wei , Mingsheng Ying

Achieving unit fidelity in quantum state preparation is often impossible in the presence of environmental decoherence. While continuous monitoring and feedback control can improve fidelity, perfect state preparation remains elusive in many…

Quantum Physics · Physics 2025-07-02 Eoin O'Connor , Hailan Ma , Marco G. Genoni

We derive a variational expression for the correlation time of physical observables in steady-state diffusive systems. As a consequence of this variational expression, we obtain lower bounds on the correlation time, which provide speed…

Statistical Mechanics · Physics 2023-03-24 Andreas Dechant , Jerome Garnier-Brun , Shin-ichi Sasa

Gate fidelity -- an average fidelity over all possible input states -- is the workhorse metric for benchmarking quantum gates or circuits, yet fault-tolerant quantum computing ultimately depends on the worst-case behavior, typically…

Quantum Physics · Physics 2026-03-10 Kyoungho Cho , Ilkwon Sohn , Yongsoo Hwang , Jeongho Bang

Fidelity is arguably the most popular figure of merit in quantum sciences. However, many of its properties are still unknown. In this work, we resolve the open problem of maximizing average fidelity over arbitrary finite ensembles of…

Quantum Physics · Physics 2022-06-17 A. Afham , Richard Kueng , Chris Ferrie

We discuss quantum fidelity decay of classically regular dynamics, in particular for an important special case of a vanishing time averaged perturbation operator, i.e. vanishing expectation values of the perturbation in the eigenbasis of…

Quantum Physics · Physics 2009-11-10 Tomaz Prosen , Marko Znidaric

Information theory has become an increasingly important research field to better understand quantum mechanics. Noteworthy, it covers both foundational and applied perspectives, also offering a common technical language to study a variety of…

Quantum Physics · Physics 2021-03-09 Diego Paiva Pires , Kavan Modi , Lucas Chibebe Céleri

The conditions under which time-energy uncertainty relations derived by Deffner and Lutz [10] for time-dependent quantum systems minimize the time necessary to excite such systems from their ground state to excited states are examined. The…

Quantum Physics · Physics 2014-10-27 Tarek Khalil , Jean Richert

In the theory of quantum transmission of information the concept of fidelity plays a fundamental role. An important class of channels, which can be experimentally realized in quantum optics, is that of Gaussian quantum channels. In this…

Quantum Physics · Physics 2009-10-31 Gh. -S. Paraoanu , H. Scutaru

We study the quantum speed limit for open quantum systems described by the Lindblad master equation. The obtained inequality shows a trade-off relation between the operation time and the physical quantities such as the energy fluctuation…

Quantum Physics · Physics 2019-01-14 Ken Funo , Naoto Shiraishi , Keiji Saito

We establish the minimum time it takes for an initial state of mean energy E and energy spread DE to move from its initial configuration by a predetermined amount. Distances in Hilbert space are estimated by the fidelity between the initial…

Quantum Physics · Physics 2009-11-07 Vittorio Giovannetti , Seth Lloyd , Lorenzo Maccone

In the context of quantum speed limits, it has been shown that the minimum time required to cause a desired state conversion via the open quantum dynamics can be estimated using the entropy production. However, the established entropy-based…

Quantum Physics · Physics 2024-10-16 Kotaro Sekiguchi , Satoshi Nakajima , Ken Funo , Hiroyasu Tajima

We study the maximum speed of quantum computation and how it is affected by limitations on physical resources. We show how the resulting concepts generalize to a broader class of physical models of computation within dynamical systems and…

Quantum Physics · Physics 2016-11-29 Benjamin Russell , Susan Stepney

We review the mathematical speed limits on quantum information processing in many-body systems. After the proof of the Lieb-Robinson Theorem in 1972, the past two decades have seen substantial developments in its application to other…

Quantum Physics · Physics 2023-10-02 Chi-Fang Chen , Andrew Lucas , Chao Yin

Protocols for discriminating between a pair of channels or for estimating a channel parameter can often be aided by adaptivity or by entanglement between the probe states. This can make it difficult to bound the best possible performance…

Quantum Physics · Physics 2021-10-07 Jason L. Pereira , Leonardo Banchi , Stefano Pirandola

In the field of quantum information theory, the concept of quantum fidelity is employed to quantify the similarity between two quantum states. It has been observed that the fidelity between two states describing a bipartite quantum system…

Quantum Physics · Physics 2023-08-01 Seong-Kun Kim , Yonghae Lee

We study the quantum speed limit time for a two-qubit system interacts with indepen- dent and common reservoir. The system is initially prepared in a class of X-structure density matrix, namely the extended Werner-like states (EWL). We…

Quantum Physics · Physics 2017-02-15 N. Behzadi , A. Ektesabi , B. Ahansaz , E. Faizi