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Related papers: Optimal quantum speed for mixed states

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The notion of quantum speed limit (QSL) refers to the fundamental fact that two quantum states become completely distinguishable upon dynamical evolution only after a finite amount time, called the QSL time. A different, but related concept…

Quantum Physics · Physics 2019-04-29 Pablo M. Poggi

In this paper, we propose a concept to use a quantum speed limit (QSL) as a measure of robustness of states, defining that a state with bigger QSL is more robust. In this perspective, it is important to have an explicitly-computable QSL,…

Quantum Physics · Physics 2020-10-21 Kohei Kobayashi , Naoki Yamamoto

The quantum speed limit specifies a universal bound of the fidelity between the initial state and the time-evolved state. We apply this method to find a bound of the fidelity between the adiabatic state and the time-evolved state. The bound…

Quantum Physics · Physics 2020-07-22 Keisuke Suzuki , Kazutaka Takahashi

In this article we propose a method to estimate with high accuracy pure quantum states of a single qudit. Our method is based on the minimization of the squared error between the complex probability amplitudes of the unknown state and its…

Quantum Physics · Physics 2021-07-14 A. Rojas , L. Pereira , S. Niklitschek , A. Delgado

The quantum speed limit sets a fundamental restriction on the evolution time of quantum systems. We explore the relationship between quantum imaginarity and the quantum speed limit by utilizing measures such as relative entropy, trace…

Quantum Physics · Physics 2025-11-11 Dong-Ping Xuan , Zhong-Xi Shen , Wen Zhou , Shao-Ming Fei , Zhi-Xi Wang

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

Setting the minimal-time bound for a quantum system to evolve between two distinguishable states, the quantum speed limit (QSL) characterizes the latent capability in speeding up of the system. It has found applications in determining the…

Quantum Physics · Physics 2023-02-02 Wei Wu , Jun-Hong An

A relevant problem in quantum computing concerns how fast a source state can be driven into a target state according to Schr\"odinger's quantum mechanical evolution specified by a suitable driving Hamiltonian. In this paper, we study in…

Quantum Physics · Physics 2020-03-18 Steven Gassner , Carlo Cafaro , Salvatore Capozziello

Quantum speed limits set the maximal pace of state evolution. Two well-known limits exist for a unitary time-independent Hamiltonian: the Mandelstam-Tamm and Margolus-Levitin bounds. The former restricts the rate according to the state…

Quantum Physics · Physics 2022-10-07 Gal Ness , Andrea Alberti , Yoav Sagi

The quantum speed limit provides fundamental bound on how fast a quantum system can evolve between the initial and the final states. For the unitary evolution, the celebrated Mandelstam-Tamm (MT) bound has been widely studied for various…

Quantum Physics · Physics 2022-08-11 Dimpi Thakuria , Arun Kumar Pati

Starting from a geometric perspective, we derive a quantum speed limit for arbitrary open quantum evolution, which could be Markovian or non-Markovian, providing a fundamental bound on the time taken for the most general quantum dynamics.…

Quantum Physics · Physics 2019-08-07 Francesco Campaioli , Felix A. Pollock , Kavan Modi

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 construct a general measure for detecting the quantum speedup in both closed and open systems. The speed measure is based on the changing rate of the position of quantum states on a manifold with appropriate monotone Riemannian metrics.…

Quantum Physics · Physics 2016-07-07 Zhen-Yu Xu

We derive generalized quantum speed limit inequalities that represent limitations on the time evolution of quantum states. They are extensions of the original inequality and are applied to the overlap between the time-evolved state and an…

Quantum Physics · Physics 2022-06-22 Kazutaka Takahashi

Quantum asymmetry and coherence are genuinely quantum resources that are essential to realize quantum advantage in information technologies. However, all quantum processes are fundamentally constrained by quantum speed limits, which raises…

Quantum Physics · Physics 2026-04-28 Agung Budiyono , Michael Moody , Hadyan L. Prihadi , Rafika Rahmawati , Sebastian Deffner

The speed limit of quantum state transfer (QST) in a system of interacting particles is not only important for quantum information processing, but also directly linked to Lieb-Robinson-type bounds that are crucial for understanding various…

Quantum Physics · Physics 2023-11-28 Casey Jameson , Bora Basyildiz , Daniel Moore , Kyle Clark , Zhexuan Gong

The state of a quantum system may be steered towards a predesignated target state, employing a sequence of weak $\textit{blind}$ measurements (where the detector's readouts are traced out). Here we analyze the steering of a two-level system…

Quantum Physics · Physics 2022-01-19 Parveen Kumar , Kyrylo Snizhko , Yuval Gefen , Bernd Rosenow

The laws of quantum physics place a limit on the speed of computation. In particular, the evolution time of a system from an initial state to a final state cannot be arbitrarily short. Bounds on the speed of evolution for unitary dynamics…

Quantum Physics · Physics 2025-07-09 Zihao Hu , Haidong Yuan , Zigui Zhang , Chi-Hang Fred Fung , Zibo Miao

Quantum speed limit is bound on the minimum time a quantum system requires to evolve from an initial state to final state under a given dynamical process. It sheds light on how fast a desired state transformation can take place which is…

Quantum Physics · Physics 2023-05-31 Vivek Pandey , Divyansh Shrimali , Brij Mohan , Siddhartha Das , Arun Kumar Pati

Non-classical features of quantum systems can degrade when subjected to environment and noise. Here, we ask a fundamental question: What is the minimum amount of time it takes for a quantum system to exhibit non-classical features in the…

Quantum Physics · Physics 2024-09-23 Divyansh Shrimali , Swapnil Bhowmick , Arun Kumar Pati