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Related papers: Optimal quantum speed for mixed states

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In this work, we address the problem of maximizing fidelity in a quantum state transformation process controlled in such a way as to keep decoherence within given bounds. We consider a three-level $\Lambda$-type atom subjected to Markovian…

Quantum Physics · Physics 2022-03-30 Nahid Binandeh Dehaghani , Fernando Lobo Pereira

We analyze the physics of optimal protocols to prepare a target state with high fidelity in a symmetrically coupled two-qubit system. By varying the protocol duration, we find a discontinuous phase transition, which is characterized by a…

Statistical Mechanics · Physics 2018-05-17 Marin Bukov , Alexandre G. R. Day , Phillip Weinberg , Anatoli Polkovnikov , Pankaj Mehta , Dries Sels

Quantum state change can not occurs instantly, but the speed of quantum evolution is limited to an upper bound value, called quantum speed limit (QSL). Engineering QSL is an important task for quantum information and computation science and…

Quantum Physics · Physics 2024-11-11 A. Aaliray , H. Mohammadi

Entanglement speeds up evolution of a pure bipartite spin state, in line with the time energy uncertainty. However if the state is mixed this is not necessarily the case. We provide a counter example and point to other factors affecting…

Quantum Physics · Physics 2009-11-13 Judy Kupferman , Benni Reznik

Utilizing the program of expectation values in coherent states and its recently developed algorithmic tools, this letter investigates the dynamical properties of cosmological coherent states for Loop Quantum Gravity. To this end, the…

General Relativity and Quantum Cosmology · Physics 2022-06-22 Klaus Liegener , Łukasz Rudnicki

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 investigate the speed of disentanglement in the multiqubit systems under the local depolarizing channel, in which each qubit is independently coupled to the environment. We focus on the bipartition entanglement between one qubit and the…

Quantum Physics · Physics 2015-03-19 Fu-Lin Zhang , Yue Jiang , Mai-Lin Liang

We introduce the concept of Magic Subspaces for the control of dissipative N- level quantum systems whose dynamics are governed by Lindblad equation. For a given purity, these subspaces can be defined as the set of density matrices for…

Quantum Physics · Physics 2020-09-16 A. A. Diaz V. , V. Martikyan , S. J. Glaser , D. Sugny

Quantum coherence, rooted in the superposition principle of quantum mechanics, is a crucial quantum resource. Various measures, operational interpretations, and generalizations of quantum coherence have been proposed. In recent years, its…

Quantum Physics · Physics 2025-04-22 Hai Wang , Ujjwal Sen

We discuss the problem of counting the maximum number of distinct states that an isolated physical system can pass through in a given period of time---its maximum speed of dynamical evolution. Previous analyses have given bounds in terms of…

Quantum Physics · Physics 2009-10-30 Norman Margolus , Lev B. Levitin

We study the problem of driving an unknown initial mixed quantum state onto a known pure state without using unitary transformations. This can be achieved, in an efficient manner, with the help of sequential measurements on at least two…

Quantum Physics · Physics 2009-11-11 L. Roa , G. Olivares

Quantum speed limit is a fundamental speed limit for the evolution of quantum states. It is the single-most important interpretation of the time energy uncertainty relation. Recently the speed limit of quantum correlations have been…

Quantum Physics · Physics 2024-11-08 Shrobona Bagchi

The speed of quantum evolution is limited under finite energy resources. While most quantum speed limits (QSLs) are formulated in terms of quantum states, they can be extended to the evolution operator itself, and thus impose fundamental…

Quantum Physics · Physics 2026-04-28 Hunter Nelson , Edwin Barnes

Quantum speed limit (QSL) is the lower bound on the time required for a state to evolve to a desired final state under a given Hamiltonian evolution. Three well-known QSLs exist Mandelstam-Tamm (MT), Margolus-Levitin (ML), and dual ML…

Quantum Physics · Physics 2024-10-21 M Suman , S. Aravinda , Ranjan Modak

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

Quantum speed limits set fundamental lower bounds on the time required for a quantum system to evolve between states. Traditional bounds, such as those by Mandelstam-Tamm and Margolus-Levitin, rely on state distinguishability and become…

Quantum Physics · Physics 2026-02-18 Ole Sönnerborn

In the Schr{\"o}dinger picture, the state of a quantum system evolves in time and the quantum speed limit describes how fast the state of a quantum system evolves from an initial state to a final state. However, in the Heisenberg picture…

Quantum Physics · Physics 2022-12-07 Brij Mohan , Arun Kumar Pati

Approximating a quantum state by the convex mixing of some given states has strong experimental significance and provides potential applications in quantum resource theory. Here we find a closed form of the minimal distance in the sense of…

Quantum Physics · Physics 2022-02-23 Li-qiang Zhang , Nan-nan Zhou , Chang-shui Yu

Quantum speed limit (QSL) is the study of fundamental limits on the evolution time of quantum systems. For instance, under the action of a time-independent Hamiltonian, the evolution time between an initial and a final quantum state obeys…

Quantum Physics · Physics 2024-05-17 H. F. Chau , Wenxin Zeng

Dissipation has traditionally been considered a hindrance to quantum information processing, but recent studies have shown that it can be harnessed to generate desired quantum states. To be useful for practical applications, the ability to…

Quantum Physics · Physics 2023-05-31 Junjie Liu , Hanlin Nie
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