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Related papers: Applications of fidelity measures to complex quant…

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Quantum technology has led to increasingly sophisticated and complex quantum devices. Assessing their reliability (quantum reliability) is an important issue. Although reliability theory for classical devices has been well developed in…

Quantum Physics · Physics 2023-10-24 L. X. Cui , Y-M. Du , C. P. Sun

We investigate the role of a statistical complexity measure to assign equilibration in isolated quantum systems. While unitary dynamics preserve global purity, expectation values of observables often exhibit equilibration-like behavior,…

Quantum Physics · Physics 2025-08-14 Marcos G. Alpino , Tiago Debarba , Reinaldo O. Vianna , André T. Cesário

In idealized models of a quantum register and its environment, quantum information can be stored indefinitely by encoding it into a decoherence-free subspace (DFS). Nevertheless, perturbations to the idealized register-environment coupling…

Quantum Physics · Physics 2019-07-03 Joris Kattemölle , Jasper van Wezel

We show that introducing a small uncertainty in the parameters of quantum systems can make the dynamics of these systems robust against perturbations. Concretely, for the case where a system is subject to perturbations due to an…

Quantum Physics · Physics 2017-11-22 Meenu Kumari , Eduardo Martin-Martinez , Achim Kempf , Shohini Ghose

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

We show that the recently introduced operator fidelity metric provides a natural tool to investigate the cross-over to quantum chaotic behaviour. This metric is an information-theoretic measure of the global stability of a unitary evolution…

Quantum Physics · Physics 2015-05-13 Paolo Giorda , Paolo Zanardi

Precision control of quantum systems is the driving force for both quantum technology and the probing of physics at the quantum and nano-scale. We propose an implementation independent method for in situ quantum control that leverages…

Quantum Physics · Physics 2015-07-14 Christopher Ferrie , Osama Moussa

We present a perturbative result for the temporal evolution of the fidelity of the quantum kicked rotor, i.e. the overlap of the same initial state evolved with two slightly different kicking strengths, for kicking periods close to a…

Quantum Physics · Physics 2011-08-10 Benedikt Probst , Remy Dubertrand , Sandro Wimberger

Spontaneous symmetry breaking mechanism in quantum phase transitions manifests the existence of degenerate groundstates in broken symmetry phases. To detect such degenerate groundstates, we introduce a quantum fidelity as an overlap…

Statistical Mechanics · Physics 2013-09-11 Yao Heng Su , Bing-Quan Hu , Sheng-Hao Li , Sam Young Cho

Quantum complexity measures the difficulty of obtaining a given state starting from a typically unentangled state. In this work, we show that complexity, when defined through the minimization of a Riemannian cost functional over the…

Quantum Physics · Physics 2025-06-05 Nadir Samos Sáenz de Buruaga

Estimating the fidelity with a target state is important in quantum information tasks. Many fidelity estimation techniques present a suitable measurement scheme to perform the estimation. In contrast, we present techniques that allow the…

Quantum Physics · Physics 2024-07-12 Akshay Seshadri , Martin Ringbauer , Jacob Spainhour , Thomas Monz , Stephen Becker

Quantum information-based approaches, in particular the fidelity, have been flexible probes for phase boundaries of quantum matter. A major hurdle to a more widespread application of fidelity and other quantum information measures to…

Strongly Correlated Electrons · Physics 2023-01-18 Miguel M. Oliveira , Pedro Ribeiro , Stefan Kirchner

Individual neutral atoms excited to Rydberg states are a promising platform for quantum simulation and quantum information processing. However, experimental progress to date has been limited by short coherence times and relatively low gate…

We consider a physical system in which the description of states and measurements follow the usual quantum mechanical rules. We also assume that the dynamics is linear, but may not be fully quantum (i.e unitary). We show that in such a…

Quantum Physics · Physics 2009-10-31 Aditi Sen De , Ujjwal Sen

We present a derivation and numerous applications of a compact explicit formula for the average fidelity of a quantum operation on a finite dimensional quantum system. The formula can be applied to averages over particularly relevant…

Quantum Physics · Physics 2009-02-26 Line Hjortshoj Pedersen , Klaus Molmer , Niels Martin Moller

Selective transfer of information between spin-1/2 particles arranged in a ring is achieved by optimizing the transfer fidelity over a readout time window via shaping, externally applied, static bias fields. Such static control fields have…

Quantum Physics · Physics 2019-10-15 Sean O'Neil , Edmond Jonckheere , Sophie Schirmer , Frank Langbein

We propose a new quantity called modulus fidelity to measure the closeness of two quantum pure states. Especially, we use it to investigate the closeness of eigenstates of quantum many-body systems. When the system is integrable, the…

Statistical Mechanics · Physics 2015-12-15 Haibin Li , Yang Yang , Pei Wang , Xiaoguang Wang

In this work, we develop an analytical framework to understand quantum friction across distinct stability regimes, providing approximate expressions for frictional forces both in the deep stable regime and near the critical threshold of…

Quantum Physics · Physics 2025-02-10 Daigo Oue , Boris Shapiro , Mário G. Silveirinha

We consider quantum fidelity between two states $\rho$ and $\sigma$, where we fix $\rho$ and allow $\sigma$ to be sent through a quantum channel. We determine the minimal fidelity where one minimizes over (a) all unital channels, (b) all…

Quantum Physics · Physics 2015-09-11 Jin Li , Rajesh Pereira , Sarah Plosker

The performance of a quantum information processing protocol is ultimately judged by distinguishability measures that quantify how distinguishable the actual result of the protocol is from the ideal case. The most prominent…

Quantum Physics · Physics 2023-07-13 Soorya Rethinasamy , Rochisha Agarwal , Kunal Sharma , Mark M. Wilde