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Related papers: Distance Bounds on Quantum Dynamics

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The correlation distance quantifies the statistical independence of two classical or quantum systems, via the distance from their joint state to the product of the marginal states. Tight lower bounds are given for the mutual information…

Quantum Physics · Physics 2013-09-23 Michael J. W. Hall

In this paper, we derive sharp lower bounds, also known as quantum speed limits, for the time it takes to transform a quantum system into a state such that an observable assumes its lowest average value. We assume that the system is…

Quantum Physics · Physics 2021-06-02 Dan Allan , Niklas Hörnedal , Ole Andersson

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

The destruction of quantum interference, decoherence, and the destruction of entanglement both appear to occur under the same circumstances. To address the connection between these two phenomena, we consider the evolution of arbitrary…

Quantum Physics · Physics 2009-11-10 P. J. Dodd , J. J. Halliwell

Dynamical decoupling techniques constitute an integral part of many quantum sensing platforms, often leading to orders-of-magnitude improvements in coherence time and sensitivity. Most AC sensing sequences involve a periodic echo-like…

We investigate the emergent open dynamics of a quantum system that undergoes rapid repeated unitary interactions with a sequence of ancillary systems. We study in detail how decoherence appears as a subleading effect when a quantum system…

Quantum Physics · Physics 2016-10-26 Daniel Grimmer , David Layden , Robert B. Mann , Eduardo Martin-Martinez

The decoherence mechanism signals the limits beyond which the system dynamics approaches the classical behavior. We show that in some cases decoherence may also signal the limits beyond which the system dynamics has to be described by…

Quantum Physics · Physics 2019-08-17 Eleonora Alfinito , Rosario G. Viglione , Giuseppe Vitiello

A quantum-classical limit of the canonical equilibrium time correlation function for a quantum system is derived. The quantum-classical limit for the dynamics is obtained for quantum systems comprising a subsystem of light particles in a…

Statistical Mechanics · Physics 2009-11-10 Alessandro Sergi , Raymond Kapral

Quantum technology resorts to efficient utilization of quantum resources to realize technique innovation. The systems are controlled such that their states follow the desired manners to realize different quantum protocols. However, the…

Quantum Physics · Physics 2021-01-13 Si-Yuan Bai , Chong Chen , Hong Wu , Jun-Hong An

We show that open-loop dynamical control techniques may be used to synthesize unitary transformations in open quantum systems in such a way that decoherence is perturbatively compensated for to a desired (in principle arbitrarily high)…

Quantum Physics · Physics 2010-07-20 Kaveh Khodjasteh , Daniel A. Lidar , Lorenza Viola

We investigate a quantum dynamical entropy of one-dimesional quantum spin systems. We show that the dynamical entropy is bounded from above by a quantity which is related with group velocity determined by the interaction and mean entropy of…

Quantum Physics · Physics 2015-06-26 Takayuki Miyadera , Masanori Ohya

We consider a closed quantum system subject to a stochastic resetting process. The generic expression for the resulting density operator is formulated for arbitrary resetting dynamics, fully characterised by the distribution of times…

Quantum Physics · Physics 2023-02-15 Francisco J. Sevilla , Andrea Valdés-Hernández

It is shown that a generalization of the fluctuation-dissipation theorem places an upper bound on the figure of merit for any quantum gate designed to entangle spatially-separated qubits. The bound depends solely on the spectral properties…

Quantum Physics · Physics 2007-05-23 A. J. Fisher

The coherence time of an electron spin decohered by the nuclear spin environment in a quantum dot can be substantially increased by subjecting the electron to suitable dynamical decoupling sequences. We analyze the performance of high-level…

Mesoscale and Nanoscale Physics · Physics 2008-03-27 Wenxian Zhang , N. P. Konstantinidis , V. V. Dobrovitski , B. N. Harmon , Lea F. Santos , Lorenza Viola

We show that quantum mechanical entanglement can prevail even in noisy open quantum systems at high temperature and far from thermodynamical equilibrium, despite the deteriorating effect of decoherence. The system consists of a number N of…

Quantum Physics · Physics 2007-05-23 L. Hartmann , W. Dür , H. -J. Briegel

We give a lower bound on the probability of error in quantum state discrimination. The bound is a weighted sum of the pairwise fidelities of the states to be distinguished.

Quantum Physics · Physics 2016-11-15 Ashley Montanaro

We investigate the effectiveness of different dynamical decoupling protocols for storage of a single qubit in the presence of a purely dephasing bosonic bath, with emphasis on comparing quantum coherence preservation under uniform vs.…

Quantum Physics · Physics 2015-05-14 Thomas E. Hodgson , Lorenza Viola , Irene D'Amico

Upper and lower bounds are established for the survival probability $|<\psi(0)|\psi(t)>|^{2}$ of a quantum state, in terms of the energy moments $<\psi(0)|H^{n}|\psi(0)>$. Introducing a cut-off in the energy generally enables considerable…

Quantum Physics · Physics 2009-11-13 Mark Andrews

We derive the continuous-time limit of discrete quantum walks with topological phases. We show the existence of a continuous-time limit that preserves their topological phases. We consider both simple-step and split-step walks, and derive…

Quantum Physics · Physics 2016-11-23 Radhakrishnan Balu , Daniel Castillo , George Siopsis , Christian Weedbrook

This paper explores the use of laboratory closed-loop learning control to either fight or cooperate with decoherence in the optimal manipulation of quantum dynamics. Simulations of the processes are performed in a Lindblad formulation on…

Quantum Physics · Physics 2007-05-23 Feng Shuang , Herschel Rabitz
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