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Related papers: Quantum speed limits for Bell-diagonal states

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Memory effects play an important role in the theory of open quantum systems. There are two completely independent insights about memory for quantum channels. In quantum information theory, the memory of the quantum channel is depicted by…

Quantum Physics · Physics 2019-05-31 N. Awasthi , S. Haseli , U. C Johri , S. Salimi , H. Dolatkhah , A. S. Khorashad

We derive algebraic bounds on achievable rates for quantum state transfer and entanglement generation in general quantum systems. We apply these bounds to graph-based models of local quantum spin systems to obtain speed limits on these…

Quantum Physics · Physics 2017-04-19 Jeffrey M. Epstein , K. Birgitta Whaley

Finding minimal time and establishing the structure of the corresponding optimal controls which can transfer a given initial state of a quantum system into a given target state is a key problem of quantum control. In this work, this problem…

Quantum Physics · Physics 2025-02-21 L. V. Lokutsievskiy , A. N. Pechen , M. I. Zelikin

We investigate the influence of an excited-state quantum phase transition (ESQPT) on the quantum speed limit (QSL) time of an open quantum system. The system consists of a central qubit coupled to a spin environment modeled by a…

Quantum Physics · Physics 2019-08-21 Qian Wang , Francisco Perez-Bernal

The quantum speed limit (QSL) time for open system characterizes the most efficient response of the system to the environmental influences. Previous results showed that the non-Markovianity governs the quantum speedup. Via studying the…

Quantum Physics · Physics 2017-04-27 Hai-Bin Liu , W. L. Yang , Jun-Hong An , Zhen-Yu Xu

This paper reports on some new inequalities of Margolus-Levitin-Mandelstam-Tamm-type involving the speed of quantum evolution between two orthogonal pure states. The clear determinant of the qualitative behavior of this time scale is the…

Quantum Physics · Physics 2015-05-14 Ulvi Yurtsever

We explore the physical limits of pulsed dynamical decoupling methods for decoherence control as determined by finite timing resources. By focusing on a decohering qubit controlled by arbitrary sequences of $\pi$-pulses, we establish a…

Quantum Physics · Physics 2011-04-11 Kaveh Khodjasteh , Tamás Erdélyi , Lorenza Viola

Recently, the notion of a quantum acceleration limit has been proposed for any unitary time evolution of quantum systems governed by arbitrary nonstationary Hamiltonians. This limit articulates that the rate of change over time of the…

Quantum Physics · Physics 2026-05-29 Carlo Cafaro , Walid Redjem , Paul M. Alsing , Newshaw Bahreyni , Christian Corda

Dissipationless localized bound states of open quantum systems are significantly robust to decoherence and have potential applications in quantum technologies. In this work, the decoherence dynamics and dissipationless localized bound…

Quantum Physics · Physics 2024-10-29 Chia-Yi Lin , Chuan-Zhe Yao , Hon-Lam Lai , Chin-Chun Tsai , Wei-Min Zhang

The problem concerning the minimum time for an initial state to evolve up to a target state plays an important role in the Classic Optimal Control theory. In the quantum context, as quantum states are so sensitive to environmental…

Quantum Physics · Physics 2015-09-01 Alexandre Coutinho Lisboa , Jose Roberto Castilho Piqueira

To implement quantum information technologies, carefully designed control for preparing a desired state plays a key role. However, in realistic situation, the actual performance of those methodologies is severely limited by decoherence.…

Quantum Physics · Physics 2025-10-02 Kohei Kobayashi

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

Given the initial and final states of a quantum system, the speed of transportation of state vector in the projective Hilbert space governs the quantum speed limit. Here, we ask the question what happens to the quantum speed limit under…

Quantum Physics · Physics 2024-08-16 Abhay Srivastav , Vivek Pandey , Arun K Pati

In systems considered for quantum computing, i.e., for control of quantum dynamics with the goal of processing information coherently, decoherence and deviation from pure quantum states, are the main obstacles to fault-tolerant error…

Mesoscale and Nanoscale Physics · Physics 2010-10-12 Vladimir Privman

One of the defining properties of an open quantum system is the variation of its purity in time. We derive speed limits on the rate of purity change for systems coupled to a Markovian environment. Our speed limits are based on Liouville…

Quantum Physics · Physics 2016-10-12 Raam Uzdin , Ronnie Kosloff

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 extend the work in New J. Phys. 19, 103015 (2017) by deriving a lower bound for the minimum time necessary to implement a unitary transformation on a generic, closed quantum system with an arbitrary number of classical control fields.…

Quantum Physics · Physics 2018-07-04 Juneseo Lee , Christian Arenz , Herschel Rabitz , Benjamin Russell

Optimal control theory is a promising candidate for a drastic improvement of the performance of quantum information tasks. We explore its ultimate limit in paradigmatic cases, and demonstrate that it coincides with the maximum speed limit…

We derive rigorous upper bounds on the distance between quantum states in an open system setting, in terms of the operator norm between the Hamiltonians describing their evolution. We illustrate our results with an example taken from…

Quantum Physics · Physics 2008-08-14 D. A. Lidar , P. Zanardi , K. Khodjasteh

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