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Related papers: Quantum Speed Limit Time in two-qubit system by Dy…

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The traditional quantum speed limits are not attainable for many physical processes, as they tend to be loose and fail to determine the exact time taken by quantum systems to evolve. To address this, we derive exact quantum speed limits for…

Quantum Physics · Physics 2023-08-30 Arun K. Pati , Brij Mohan , Sahil , Samuel L. Braunstein

We propose a selective dynamical decoupling scheme on a chain of permanently coupled qubits with XX type interactions, which is capable of dynamically suppressing any coupling in the chain by applying sequences of local pulses to the…

Quantum Physics · Physics 2015-12-16 Holger Frydrych , Michael Marthaler , Gernot Alber

The characterization and mitigation of decoherence in natural and artificial two-level systems (qubits) is fundamental to quantum information science and its applications. Decoherence of a quantum superposition state arises from the…

Dynamical decoupling (DD) is a low-overhead method for quantum error suppression. Despite extensive work in DD design, finding pulse sequences that optimally decouple computational qubits on noisy quantum hardware is not well understood. In…

Quantum Physics · Physics 2026-04-22 Christopher Tong , Helena Zhang , Bibek Pokharel

Bounds to the speed of evolution of a quantum system are of fundamental interest in quantum metrology, quantum chemical dynamics and quantum computation. We derive a time-energy uncertainty relation for open quantum systems undergoing a…

Quantum Physics · Physics 2013-03-05 A. del Campo , I. L. Egusquiza , M. B. Plenio , S. F. Huelga

We derive Margolus-Levitin and Mandelstamm-Tamm type bound on the quantum speed limit time for the creation and decay of quantum correlations by an amount in a quantum system evolving under the influence of its ambient environment. The…

Quantum Physics · Physics 2022-05-25 K. G Paulson , Subhashish Banerjee

The evaluation of the minimal evolution time between two distinguishable states of a system is important for assessing the maximal speed of quantum computers and communication channels. Lower bounds for this minimal time have been proposed…

Quantum Physics · Physics 2013-02-01 M. M. Taddei , B. M. Escher , L. Davidovich , R. L. de Matos Filho

Reducing decoherence is an essential step toward realizing general-purpose quantum computers beyond the present noisy intermediate-scale quantum (NISQ) computers. To this end, dynamical decoupling (DD) approaches in which external fields…

Quantum Physics · Physics 2022-09-23 Yukiyoshi Ohtsuki , Suicho Mikami , Toru Ajiki , David J. Tannor

Using the approach offered by quantum speed limit, we show that geometric measure of multipartite entanglement for pure states [Phys. Rev. A 68, 042307(2003)] can be interpreted as the minimal time necessary to unitarily evolve a given…

Quantum Physics · Physics 2021-09-29 Łukasz Rudnicki

The maximal evolution speed of any quantum system can be expressed by the quantum speed limit time. In this paper, we consider a model in which the system has a correlation with the environment. The influence of the initial correlation…

Quantum Physics · Physics 2023-07-21 Alireza Gholizadeh , Maryam Hadipour , Soroush Haseli , Saeed Haddadi , Hazhir Dolatkhah

A unified bound on the quantum speed limit is obtained for open quantum systems with the mixed initial state by utilizing the function of relative purity proposed in [Phys. Rev. Lett. 120, 060409 (2018)]. As applications, it is found that…

Quantum Physics · Physics 2018-10-31 Shao-xiong Wu , Chang-shui Yu

We investigate the pure dephasing of a Josephson qubit due to the spectral diffusion of two-level systems that are close to resonance with the qubit. We identify the parameter regime in which this pure dephasing rate can be of the order of…

Quantum Physics · Physics 2024-05-02 Shlomi Matityahu , Alexander Shnirman , Moshe Schechter

Dynamical decoupling (DD) is a powerful method for controlling arbitrary open quantum systems. In quantum spin control, DD generally involves a sequence of timed spin flips ($\pi$ rotations) arranged to average out or selectively enhance…

In this work, we obtain an analytical representation of the density operator of an atom in dissipative cavity when the reservoir is at zero temperature and the total number of excitation is N=1. We also investigated the quantum speed limit…

Quantum Physics · Physics 2020-07-21 Hong-Mei Zou , Jianhe Yang , Danping Lin , Mao-Fa Fang

Theoretically understanding and experimentally characterizing and modifying the underlying Hamiltonian of a quantum system is of utmost importance in achieving high-fidelity quantum gates for quantum computing. In this work, we explore the…

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 consider the implementation of two-qubit gates when the physical systems used to realize the qubits possess additional quantum states in the accessible energy range. We use optimal control theory to determine the maximum achievable gate…

Quantum Physics · Physics 2022-04-26 Sahel Ashhab , Fumiki Yoshihara , Tomoko Fuse , Naoki Yamamoto , Adrian Lupascu , Kouichi Semba

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 performance of a wide range of quantum computing algorithms and protocols depends critically on the fidelity and speed of the employed qubit readout. Examples include gate sequences benefiting from mid-circuit, real-time,…

We introduce a protocol that modifies dynamical decoupling (DD) sequences to be robust to static $ZZ$ crosstalk when implemented with bounded control on two-colorable qubit topologies. The protocol, which relies on modifications to the…

Quantum Physics · Physics 2025-06-24 Ethan Hickman , Xiaodi Wu , Gregory Quiroz