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Related papers: Quantum speed limit for a mixed initial state

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We establish a comprehensive theoretical framework for coherent quantum speed limits (QSLs), deriving fundamental bounds on the rate of quantum evolution that explicitly isolate the contribution of quantum coherence. By applying H\"older's…

Quantum Physics · Physics 2026-03-25 Xuhui Xiao , Hai Wang , Xingze Qiu

The preparation of quantum many-body systems faces the difficulty that in a realistic scenario only few control parameters of the system may be accessible. In this context, an interesting connection between the energy fluctuations during…

Quantum Physics · Physics 2025-08-29 Maximilian Goll , Robert H. Jonsson

We investigate the issue of speed-up and the necessity of entanglement in Grover's quantum search algorithm. We find that in a pure state implementation of Grover's algorithm entanglement is present even though the initial and target states…

Quantum Physics · Physics 2007-05-23 Samuel L. Braunstein , Arun K. Pati

Quantum coherence allows the computation of an arbitrary number of distinct computational paths in parallel. Based on quantum parallelism it has been conjectured that exponential or even larger speedups of computations are possible. Here it…

High Energy Physics - Theory · Physics 2007-05-23 K. Svozil

Experimental attempts to implement quantum speedup of computations over the past 30 years have yielded a negative result, despite the absence of physical laws prohibiting such speedup. The article formulates the limitation of quantum…

Quantum Physics · Physics 2019-10-07 Yuri Ozhigov

We prove that the time required for sustained information scrambling in any Hamiltonian quantum system is universally at least logarithmic in the entanglement entropy of scrambled states. This addresses two foundational problems in…

Quantum Physics · Physics 2024-04-25 Amit Vikram , Laura Shou , Victor Galitski

We studied geometric quantum speed limits (QSL) of a qubit subject to decoherence in an ensemble of chloroform molecules in a Nuclear Magnetic Resonance experiment. The QSL is a fundamental lower bound on the evolution time for quantum…

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

Information theory has become an increasingly important research field to better understand quantum mechanics. Noteworthy, it covers both foundational and applied perspectives, also offering a common technical language to study a variety of…

Quantum Physics · Physics 2021-03-09 Diego Paiva Pires , Kavan Modi , Lucas Chibebe Céleri

We probe the quantum speed limit (QSL) of an electron when it is trapped in a non-uniform magnetic field. We show that the QSL increases to a large value, but within the regime of causality, by choosing a proper variation in magnetic…

Quantum Physics · Physics 2022-08-26 Srishty Aggarwal , Subhashish Banerjee , Arindam Ghosh , Banibrata Mukhopadhyay

We discuss a class of quantum speed limits (QSLs) based on unified quantum ($\alpha,\mu$)-entropy for nonunitary physical processes. The bounds depend on both the Schatten speed and the smallest eigenvalue of the evolved state, and the…

Quantum Physics · Physics 2022-07-06 Diego Paiva Pires

We review the mathematical speed limits on quantum information processing in many-body systems. After the proof of the Lieb-Robinson Theorem in 1972, the past two decades have seen substantial developments in its application to other…

Quantum Physics · Physics 2023-10-02 Chi-Fang Chen , Andrew Lucas , Chao Yin

We discuss quantum speed limits (QSLs) for finite-dimensional quantum systems undergoing general physical processes. These QSLs were obtained using Schatten $\alpha$-norms, firstly exploiting geometric features of the quantum state space,…

Quantum Physics · Physics 2025-07-23 Alberto J. B. Rosal , Diogo O. Soares-Pinto , Diego Paiva Pires

We measure the quantum speed of the state evolution of the field in a weakly-driven optical cavity QED system. To this end, the mode of the electromagnetic field is considered as a quantum system of interest with a preferential coupling to…

Quantum Physics · Physics 2015-06-18 A. D. Cimmarusti , Z. Yan , B. D. Patterson , L. P. Corcos , L. A. Orozco , S. Deffner

Bounds analogous to entropic uncertainty relations allow one to design practical tests to detect quantum entanglement by a collective measurement performed on several copies of the state analyzed. This approach, initially worked out for…

Quantum Physics · Physics 2013-01-04 Łukasz Rudnicki , Zbigniew Puchała , Paweł Horodecki , Karol Życzkowski

The thermodynamic limit of the internal energy and the entropy of the system of quantum interacting particles in random medium is shown to exist under the crucial requirements of stability and temperedness of interactions. The energy turns…

Mathematical Physics · Physics 2012-01-24 Nikolaj A. Veniaminov

We discuss a model for quantum computing with initially mixed states. Although such a computer is known to be less powerful than a quantum computer operating with pure (entangled) states, it may efficiently solve some problems for which no…

Quantum Physics · Physics 2015-03-17 Michael Siomau , Stephan Fritzsche

Fundamental trade-off relations, such as quantum speed limit and quantum thermodynamic uncertainty relation, describe the performance limits of quantum systems by imposing that improvements in speed or precision necessitate a substantial…

Quantum Physics · Physics 2025-09-30 Hayato Yunoki , Yoshihiko Hasegawa

We consider a two-level open quantum system undergoing either pure dephasing, dissipative, or multiply decohering dynamics and show that, whenever the dynamics is non-Markovian, the initial speed of evolution is a monotonic function of the…

Quantum Physics · Physics 2017-07-12 Marco Cianciaruso , Sabrina Maniscalco , Gerardo Adesso

Limitations to the speed of evolution of quantum systems, typically referred to as quantum speed limits (QSLs), have important consequences for quantum control problems. However, in its standard formulation, is not straightforward to obtain…

Quantum Physics · Physics 2022-01-06 Pablo M. Poggi
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