English
Related papers

Related papers: $\mathcal{PT}$-symmetric mapping of three states a…

200 papers

Uhlmann's theorem is a central result in quantum information theory, which associates the closeness of two quantum states with that of their purifications. The theorem also well characterizes a fundamental task: how close a pure quantum…

Quantum Physics · Physics 2025-11-04 Takeru Utsumi , Yoshifumi Nakata , Qisheng Wang , Ryuji Takagi

In light of recently proposed quantum algorithms that incorporate symmetries in the hope of quantum advantage, we show that with symmetries that are restrictive enough, classical algorithms can efficiently emulate their quantum counterparts…

Quantum Physics · Physics 2023-11-29 Eric R. Anschuetz , Andreas Bauer , Bobak T. Kiani , Seth Lloyd

Non-hermitian, $\mathcal{PT}$-symmetric Hamiltonians, experimentally realized in optical systems, accurately model the properties of open, bosonic systems with balanced, spatially separated gain and loss. We present a family of exactly…

Quantum Physics · Physics 2015-12-17 Kaustubh S. Agarwal , Rajeev K. Pathak , Yogesh N. Joglekar

We present a new approach to quantum computation involving the geometric phase. In this approach, an entire computation is performed by adiabatically evolving a suitably chosen quantum system in a closed circuit in parameter space. The…

Quantum Physics · Physics 2007-05-23 David R. Mitchell

We present two new aspects for the recently proposed algorithms for matrix manipulating based on the special encoding the matrix elements into the superposition state of a quantum system. First aspect is the controlled measurement which…

Quantum Physics · Physics 2025-01-28 Edward B. Fel'dman , Alexander I. Zenchuk , Wentao Qi , Junde Wu

The quest for the realization of effective quantum state discrimination strategies is of great interest for quantum information technology, as well as for fundamental studies. Therefore, it is crucial to develop new and more efficient…

Quantum ptychography is a method for estimating an unknown pure quantum state by subjecting it to overlapping projections, each one followed by a projective measurement on a single prescribed basis. Here, we present a comprehensive study of…

Quantum Physics · Physics 2024-12-04 Warley M. S. Alves , Leonardo Neves

We review the methodology to theoretically treat parity-time- ($\mathcal{PT}$-) symmetric, non-Hermitian quantum many-body systems... (For the full abstract see paper)

Quantum Physics · Physics 2023-11-17 Volker Meden , Lukas Grunwald , Dante M. Kennes

The discrimination of non-orthogonal quantum states with reduced or without errors is a fundamental task in quantum measurement theory. In this work, we investigate a quantum measurement strategy capable of discriminating two coherent…

Quantum Physics · Physics 2010-10-12 Christoffer Wittmann , Ulrik L. Andersen , Gerd Leuchs

Quantum technologies exploit entanglement to enhance various tasks beyond their classical limits including computation, communication and measurements. Quantum metrology aims to increase the precision of a measured quantity that is…

Quantum Physics · Physics 2020-08-25 Bálint Koczor , Suguru Endo , Tyson Jones , Yuichiro Matsuzaki , Simon C. Benjamin

Searching for non-Hermitian (parity-time)$\mathcal{PT}$-symmetric Hamiltonians \cite{bender} with real spectra has been acquiring much interest for fourteen years. In this article, we have introduced a $\mathcal{PT}$ symmetric non-Hermitian…

Quantum Physics · Physics 2014-06-13 Özlem Yeşiltaş

We study the dynamics of correlations in a paradigmatic setup to observe $\mathcal{PT}$-symmetric physics: a pair of coupled oscillators, one subject to a gain one to a loss. Starting from a coherent state, quantum correlations (QCs) are…

An optimal estimator of quantum states based on a modified Kalman Filter is presented in this work. Such estimator acts after state measurement, allowing to obtain an optimal estimation of quantum state resulting in the output of any…

Quantum Physics · Physics 2014-06-20 Mario Mastriani

Qubit-based variational quantum algorithms have undergone rapid development in recent years but still face several challenges. In this context, we propose a symmetry-enhanced digitized counterdiabatic quantum algorithm utilizing qudits…

Recently, much research has been carried out on Hamiltonians that are not Hermitian but are symmetric under space-time reflection, that is, Hamiltonians that exhibit PT symmetry. Investigations of the Sturm-Liouville eigenvalue problem…

High Energy Physics - Theory · Physics 2007-05-23 Carl M. Bender , Dorje C. Brody , Lane P. Hughston , Bernhard K. Meister

We investigate the performance of error mitigation via measurement of conserved symmetries on near-term devices. We present two protocols to measure conserved symmetries during the bulk of an experiment, and develop a zero-cost…

Quantum Physics · Physics 2019-01-03 X. Bonet-Monroig , R. Sagastizabal , M. Singh , T. E. O'Brien

A new method is developed to derive an algebraic equations for the geometric measure of entanglement of three qubit pure states. The equations are derived explicitly and solved in cases of most interest. These equations allow oneself to…

Quantum Physics · Physics 2008-03-01 Levon Tamaryan , DaeKil Park , Sayatnova Tamaryan

In recent reports, suggestions have been put forward to the effect that parity and time-reversal (PT) symmetry in quantum mechanics is incompatible with causality. It is shown here, in contrast, that PT-symmetric quantum mechanics is fully…

Quantum Physics · Physics 2016-04-07 Dorje C. Brody

Quantum computing is seeking to realize hardware-optimized algorithms for application-related computational tasks. NP (nondeterministic-polynomial-time) is a complexity class containing many important but intractable problems like the…

Quantum Physics · Physics 2021-08-27 Aonan Zhang , Hao Zhan , Junjie Liao , Kaimin Zheng , Tao Jiang , Minghao Mi , Penghui Yao , Lijian Zhang

We describe a method that allows for a practical application of the theory of pseudo-Hermitian operators to PT-symmetric systems defined on a complex contour. We apply this method to study the Hamiltonians $H=p^2+x^2(ix)^\nu$ with…

Quantum Physics · Physics 2007-05-23 Ali Mostafazadeh
‹ Prev 1 8 9 10 Next ›