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Related papers: Purity Speed Limit of Open Quantum Systems from Ma…

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Precisely characterizing and controlling realistic open quantum systems is one of the most challenging and exciting frontiers in quantum sciences and technologies. In this Letter, we present methods of approximately computing reachable sets…

Quantum Physics · Physics 2016-07-13 Jun Li , Dawei Lu , Zhihuang Luo , Raymond Laflamme , Xinhua Peng , Jiangfeng Du

This paper investigates the fast Hamiltonian control of $n=2$ density operators by continuously varying the flag as one moves away from the completely mixed state. In general, the critical points and zeros of the purity derivative can only…

Quantum Physics · Physics 2016-07-06 Patrick Rooney , Anthony M. Bloch , C. Rangan

Dissipative systems with decoherence free subspaces, a.k.a. dark spaces (DSs), can be used to protect quantum information. At the same time, dissipation is expected to give rise to coherent information degradation outside the DS. Employed…

Quantum Physics · Physics 2025-05-29 Raul A. Santos , Alex Kamenev , Yuval Gefen

Unitary control and decoherence appear to be irreconcilable in quantum mechanics. When a quantum system interacts with an environment, control strategies usually fail due to decoherence. In this letter, we propose a time-optimal unitary…

Quantum Physics · Physics 2013-02-20 P. M. Poggi , F. C. Lombardo , D. A. Wisniacki

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

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

Quantum theory sets a bound on the minimal time evolution between initial and target states. This bound is called as quantum speed limit time. It is used to quantify maximal speed of quantum evolution. The quantum evolution will be faster,…

Quantum Physics · Physics 2019-07-22 S. Haseli , S. Salimi , H. Dolatkhah , A. S. Khorashad

We study the constraints imposed on the population and phase relaxation rates by the physical requirement of completely positive evolution for open N-level systems. The Lindblad operators that govern the evolution of the system are…

Quantum Physics · Physics 2009-11-10 Sonia G Schirmer , Allan I Solomon

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

In this paper, we investigate the unified bound of quantum speed limit time in open systems based on the modified Bures angle. This bound is applied to the damped Jaynes-Cummings model and the dephasing model, and the analytical quantum…

Quantum Physics · Physics 2020-03-31 Shao-xiong Wu , Chang-shui Yu

Quantum speed limits are the boundaries that define how quickly one quantum state can transform into another. Instead of focusing on the transformation between pairs of states, we provide bounds on the speed limit of quantum evolution by…

Quantum Physics · Physics 2025-11-10 Abolfazl Farmanian , Vahid Karimipour

We put forth a new class of quantum master equations that correctly reproduce the asymptotic state of an open quantum system beyond the infinitesimally weak system-bath coupling limit. Our method is based on incorporating the knowledge of…

Quantum Physics · Physics 2022-11-10 Tobias Becker , Alexander Schnell , Juzar Thingna

This article considers some control problems for closed and open two-level quantum systems. The closed system's dynamics is governed by the Schr\"odinger equation with coherent control. The open system's dynamics is governed by the…

Quantum Physics · Physics 2023-12-01 Oleg V. Morzhin , Alexander N. Pechen

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

We analyze the efficiency of protocols for adiabatic quantum state transfer assisted by an engineered reservoir. The target dynamics is a quantum trajectory in the Hilbert space and is a fixed point of a time-dependent master equation in…

Quantum Physics · Physics 2024-07-31 Emma C. King , Luigi Giannelli , Raphaël Menu , Johannes N. Kriel , Giovanna Morigi

The article considers a two-level open quantum system whose dynamics is driven by a combination of coherent and incoherent controls. Coherent control enters into the Hamiltonian part of the dynamics whereas incoherent control enters into…

Quantum Physics · Physics 2019-09-24 Oleg V. Morzhin , Alexander N. Pechen

Along with the scaling of dimensions in quantum systems, transitions between the system's energy levels would become close in frequency, which are conventionally resolved by weak and lengthy pulses. Here, we extend and experimentally…

The Lindblad equation determines the time evolution of the density operator of open quantum systems. While valid for any system size, its use is, in practice, restricted to prototype/surrogate models with the aim of tackling specific…

Quantum Physics · Physics 2026-04-07 Benedikt M. Reible , Somayeh Ahmadkhani , Luigi Delle Site

We study optimization of fidelity for ultrafast transformation of a spin chain via external control of a local exchange coupling. We show that infidelity of such a process can be dramatically decreased by choosing a proper control profile…

Quantum Physics · Physics 2019-12-11 P. V. Pyshkin , E. Ya. Sherman , Lian-Ao Wu

Quantum sensors capitalize on advanced control sequences for maximizing sensitivity and precision. However, protocols are not usually optimized for temporal resolution. Here, we establish the limits for time-resolved sensing of dynamical…

Quantum Physics · Physics 2024-12-12 Konstantin Herb , Christian L. Degen
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