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Related papers: Some geometric interpretations of quantum fidelity

200 papers

Determining the optimal fidelity for the transmission of quantum information over noisy quantum channels is one of the central problems in quantum information theory. Recently, [Berta-Borderi-Fawzi-Scholz, Mathematical Programming, 2021]…

Quantum Physics · Physics 2026-04-21 Yeow Meng Chee , Hoang Ta , Van Khu Vu

We introduce and study a one-parameter family of fidelity-type quantities based on the weighted spectral geometric mean, which we call the \emph{weighted spectral fidelity} \(…

Functional Analysis · Mathematics 2026-05-19 Cong Trinh Le , The Khoi Vu , Minh Toan Ho , Trung Hoa Dinh

Kicked atoms under a constant Stark or gravity field are investigated for experimental setups with cold and ultra cold atoms. The parametric stability of the quantum dynamics is studied using the fidelity. In the case of a quantum…

Quantum Physics · Physics 2012-03-15 Rémy Dubertrand , Italo Guarneri , Sandro Wimberger

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

We examine the physical significance of fidelity as a measure of similarity for Gaussian states, by drawing a comparison with its classical counterpart. We find that the relationship between these classical and quantum fidelities is not…

Quantum Physics · Physics 2015-06-26 H. Jeong , T. C. Ralph , W. P. Bowen

When flat or on a firm mechanical substrate, the atomic composition and atomistic structure of two-dimensional crystals dictate their chemical, electronic, optical, and mechanical properties. These properties change when the two-dimensional…

Mesoscale and Nanoscale Physics · Physics 2014-02-27 Alejandro A. Pacheco Sanjuan , Mehrshad Mehboudi , Edmund O. Harriss , Humberto Terrones , Salvador Barraza-Lopez

We present an optimal quantum algorithm for fidelity estimation between two quantum states when one of them is pure. In particular, the (square root) fidelity of a mixed state to a pure state can be estimated to within additive error…

Quantum Physics · Physics 2025-10-03 Wang Fang , Qisheng Wang

Entanglement fidelity quantifies how well a quantum channel preserves the correlations between a transmitted system and an inaccessible reference system. We derive closed-form expressions for the entanglement fidelity associated with…

Quantum Physics · Physics 2026-03-10 Niccolò Zanieri , Marios Kountouris

We present quantum fidelity benchmarks for continuous-variable (CV) quantum devices to outperform quantum channels which can transmit at most $k$-dimensional coherences for positive integers $k$. We determine an upper bound of an average…

Quantum Physics · Physics 2016-06-06 Ryo Namiki

We show that the manifold of quantum states is endowed with a rich and nontrivial geometric structure. We derive the Fubini-Study metric of the projective Hilbert space of a multi-qubit quantum system, endowing it with a Riemannian metric…

Quantum Physics · Physics 2024-04-19 Arthur Vesperini , Ghofrane Bel-Hadj-Aissa , Lorenzo Capra , Roberto Franzosi

We investigate quantum teleportation through noisy quantum channels by solving analytically and numerically a master equation in the Lindblad form. We calculate the fidelity as a function of decoherence rates and angles of a state to be…

Quantum Physics · Physics 2009-11-07 Sangchul Oh , Soonchil Lee , Hai-woong Lee

To perform reliable quantum computation, quantum error correction is indispensable. In certain cases, continuous covariance symmetry of the physical system can make exact error correction impossible. In this work we study the approximate…

Quantum Physics · Physics 2023-08-25 Hao Dai

We derive a computable analytical formula for the quantum fidelity between two arbitrary multimode Gaussian states which is simply expressed in terms of their first- and second-order statistical moments. We also show how such a formula can…

Quantum Physics · Physics 2015-12-23 Leonardo Banchi , Samuel L. Braunstein , Stefano Pirandola

Entanglement serves as a fundamental resource for various quantum information processing tasks. Fidelity of entanglement (which measures the proximity to a maximally entangled state) and various quantum entropies are key indicators for…

Quantum Physics · Physics 2025-10-21 Komal Kumar , Bivas Mallick , Tapaswini Patro , Nirman Ganguly

We associate to every quantum channel $T$ acting on a Hilbert space $\mathcal{H}$ a pair of Hamiltonian operators over the symmetric subspace of $\mathcal{H}^{\otimes 2}$. The expectation values of these Hamiltonians over symmetric product…

Quantum Physics · Physics 2007-05-23 Paolo Zanardi , Daniel Lidar

A quantum ensemble $\{(p_x, \rho_x)\}$ is a set of quantum states each occurring randomly with a given probability. Quantum ensembles are necessary to describe situations with incomplete a priori information, such as the output of a…

Quantum Physics · Physics 2009-03-30 Ognyan Oreshkov , John Calsamiglia

It is shown that the fidelity, a basic notion of quantum information science, may be used to characterize quantum phase transitions, regardless of what type of internal order is present in quantum many-body states. If the fidelity of two…

Statistical Mechanics · Physics 2007-05-23 Huan-Qiang Zhou , John Paul Barjaktarevic

We analyse the problem of finding sets of quantum states that can be deterministically discriminated. From a geometric point of view this problem is equivalent to that of embedding a simplex of points whose distances are maximal with…

Quantum Physics · Physics 2008-06-09 D. Markham , J. A. Miszczak , Z. Puchala , K. Zyczkowski

We give an alternative definition of quantum fidelity for two density operators on qudits in terms of the Hilbert-Schmidt inner product between them and their purity. It can be regarded as the well-defined operator fidelity for the two…

Quantum Physics · Physics 2009-11-13 Xiaoguang Wang , Chang-Shui Yu , X. X. Yi

General properties of quantum systems which interact with stochastic environment are studied with a strong emphasis on the role of physical symmetries. The similarity between the fidelity which is used to characterize the stability of such…

High Energy Physics - Theory · Physics 2007-05-23 V. I. Kuvshinov , P. V. Buividovich