English
Related papers

Related papers: Noncompletely Positive Quantum Maps Enable Efficie…

200 papers

Positive maps are useful for detecting entanglement in quantum information theory. Any entangled state can be detected by some positive map. In this paper, the relation between positive block matrices and completely positive…

Mathematical Physics · Physics 2013-06-14 Yu Guo , Heng Fan

Work extraction protocol is always a significant issue in the context of quantum batteries, in which the notion of ergotropy is used to quantify a particular amount of energy that can be extracted through unitary processes. Given the total…

Quantum Physics · Physics 2021-10-04 F. H. Kamin , S. Salimi , Alan C. Santos

The ultimate goal of this paper is to develop a systematic method for deriving quantum master equations that satisfy the requirements of a completely positive and trace-preserving (CPTP) map, further describing thermal relaxation processes.…

Quantum Physics · Physics 2024-11-15 F. Nicacio , T. Koide

The ability of fully reconstructing quantum maps is a fundamental task of quantum information, in particular when coupling with the environment and experimental imperfections of devices are taken into account. In this context we carry out a…

Quantum Physics · Physics 2010-11-04 I. Bongioanni , L. Sansoni , F. Sciarrino , G. Vallone , P. Mataloni

Going beyond isolated system dynamics, we examine how local and spatially correlated reservoirs influence the work extraction in quantum batteries. By employing a one-dimensional spin-1/2 model coupled to baths via dephasing and…

Quantum Physics · Physics 2025-09-30 Sejal Ahuja , Tanoy Kanti Konar , Aditi Sen De

We discuss the idea of extracting energy from a quantum battery, applying a projective measurement on an auxiliary system. The battery is initially connected to the auxiliary system and allowed to interact with it. After some time, we…

Quantum Physics · Physics 2025-12-25 Paranjoy Chaki , Aparajita Bhattacharyya , Kornikar Sen , Ujjwal Sen

We establish an exponentially decaying upper bound on the average energy that can be extracted in quantum energy teleportation (QET) protocols executed on finite-range {gapped} lattice systems possessing a unique ground state. Under mild…

Quantum Physics · Physics 2026-03-31 Taisanul Haque

In the quantum world, the process of energy storage can be enhanced thanks to various nonclassical phenomena. This inspiring fact suggests quantum batteries as plausible sources of power for future quantum devices, at least in principle.…

Quantum Physics · Physics 2025-10-27 C. A. Downing , M. S. Ukhtary

We introduce a generalization of the set of completely positive matrices that we call "pairwise completely positive" (PCP) matrices. These are pairs of matrices that share a joint decomposition so that one of them is necessarily positive…

Quantum Physics · Physics 2019-05-30 Nathaniel Johnston , Olivia MacLean

We investigate the evolution of open quantum systems in the presence of initial correlations with an environment. Here the standard formalism of describing evolution by completely positive trace preserving (CPTP) quantum operations can fail…

Quantum Physics · Physics 2016-09-08 Christopher J. Wood

Quantum entanglement is considered, by and large, to be a very delicate and non-robust phenomenon that is very hard to maintain in the presence of noise, or non-zero temperatures. In recent years however, and motivated, in part, by a quest…

Quantum Physics · Physics 2017-02-27 Lior Eldar

We present a theoretical analysis of the energy recovery efficiency for quantum batteries composed of many identical quantum cells undergoing noise. While the possibility of using quantum effects to speed up the charging processes of…

Quantum Physics · Physics 2024-08-14 Salvatore Tirone , Raffaele Salvia , Stefano Chessa , Vittorio Giovannetti

We investigate a quantum battery made of N two-level systems, which is charged by an optical mode via an energy-conserving interaction. We quantify the fraction E(N) of energy stored in the B battery that can be extracted in order to…

Energy can be stored in quantum batteries by electromagnetic fields as chargers. In this paper, the performance of a quantum battery with single and double chargers is studied. It is shown that by using two independent charging fields,…

Quantum Physics · Physics 2022-12-21 Mohammad B. Arjmandi , Abbas Shokri , Esfandyar Faizi , Hamidreza Mohammadi

A quantum system which can store energy, and from which one can extract useful work, is known as a quantum battery. Such a device raises interesting issues surrounding how quantum physics can provide certain advantages in the charging,…

Quantum Physics · Physics 2024-05-21 C. A. Downing , M. S. Ukhtary

Generalized measurement schemes on one part of bipartite states, which would leave the set of all separable states insensitive are explored here to understand quantumness of correlations in a more general perspecitve. This is done by…

Quantum Physics · Physics 2012-01-04 A. R. Usha Devi , A. K. Rajagopal , Sudha

In realistic open-system environments, decoherence and dissipation naturally drive quantum batteries toward passive states, thereby limiting their maximum extractable work (ergotropy). While quantum catalysis has been proposed to mitigate…

Quantum Physics · Physics 2026-04-29 Shun-Cai Zhao

Positive maps applied to a subsystem of a bipartite quantum state constitute a central tool in characterising entanglement. In the multipartite case, however, the direct application of a positive but not completely positive map cannot…

Quantum Physics · Physics 2017-08-16 Fabien Clivaz , Marcus Huber , Ludovico Lami , Gláucia Murta

For any local Hamiltonian H, I construct a local CPT map and stopping condition which converges to the ground state subspace of H. Like any ground state preparation algorithm, this algorithm necessarily has exponential run-time in general…

Quantum Physics · Physics 2023-09-25 Toby S. Cubitt

The problem of bound entanglement detection is a challenging aspect of quantum information theory for higher dimensional systems. Here, we propose an indecomposable positive map for two-qutrit systems, which is shown to generate a class of…