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Related papers: A note on Decoherence and Fractal Hamiltonians

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In the framework of the Lindblad theory for open quantum systems we determine the degree of quantum decoherence and classical correlations of a harmonic oscillator interacting with a thermal bath. The transition from quantum to classical…

Quantum Physics · Physics 2009-11-13 A. Isar , W. Scheid

Most discussions of decoherence in the literature consider the high-temperature regime but it is also known that, in the presence of dissipation, decoherence can occur even at zero temperature. Whereas most previous investigations all…

Quantum Physics · Physics 2009-11-10 G. W. Ford , R. F. O'Connell

We provide a theoretical set up for studying the dynamics in quantum spin chain models with inhomogeneous two-body interaction. We frame in our formalism models that can be mapped into a fermion system with a quadratic Hamiltonian. Local…

Quantum Physics · Physics 2015-05-20 Giuseppe Genovese

We theoretically study the decoherence and the dynamical decoupling control of nitrogen-vacancy center electron spins in high-purity diamond, where the hyperfine interaction with $^{13}$C nuclear spins is the dominating decoherence…

Mesoscale and Nanoscale Physics · Physics 2015-03-19 Nan Zhao , Sai-Wah Ho , Ren-Bao Liu

We analyze decoherence-free (DF) quantum information in the presence of an arbitrary non-nearest-neighbor bath-induced system Hamiltonian using a Markovian master equation. We show that the most appropriate encoding for N qubits is probably…

Quantum Physics · Physics 2008-06-25 Peter G. Brooke , James D. Cresser , Manas K. Patra

Decoherence of quantum objects is critical to modern quantum sciences and technologies. It is generally believed that stronger noises cause faster decoherence. Strikingly, recent theoretical research discovers the opposite case for spins in…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 Pu Huang , Xi Kong , Nan Zhao , Fazhan Shi , Pengfei Wang , Xing Rong , Ren-Bao Liu , Jiangfeng Du

This article analyzes the decoherence induced on a single qubit by the interaction with a spin chain with nontrivial internal dynamics (XY-type interactions). The aim of the paper is to study the existence and properties of the so-called…

Quantum Physics · Physics 2008-03-31 Cecilia Cormick , Juan Pablo Paz

The superconducting flux qubit has two quantum states with opposite magnetic flux. Environment of nuclear spins can find out the direction of the magnetic flux after a decoherence time $\tau_0$ inversely proportional to the magnitude of the…

Other Condensed Matter · Physics 2009-11-10 Jacek Dziarmaga

Conventional approaches for controlling open quantum systems use coherent control which affects the system's evolution through the Hamiltonian part of the dynamics. Such control, although being extremely efficient for a large variety of…

Quantum Physics · Physics 2009-05-04 Alexander Pechen , Herschel Rabitz

Understanding and protecting the coherence of individual quantum systems is a central challenge in quantum science and technology. Over the last decades, a rich variety of methods to extend coherence have been developed. A complementary…

We study measures of decoherence and thermalization of a quantum system $S$ in the presence of a quantum environment (bath) $E$. The whole system is prepared in a canonical thermal state at a finite temperature. Applying perturbation theory…

Statistical Mechanics · Physics 2016-03-23 M. A. Novotny , F. Jin , S. Yuan , S. Miyashita , H. De Raedt , K. Michielsen

Enhancing interactions in many-body quantum systems, while protecting them from environmental decoherence, is at the heart of many quantum technologies. Waveguide quantum electrodynamics is a promising platform for achieving this, as it…

Quantum Physics · Physics 2024-05-31 Aviv Karnieli , Offek Tziperman , Charles Roques-Carmes , Shanhui Fan

Quantum information requires protection from the adverse affects of decoherence and noise. This review provides an introduction to the theory of decoherence-free subspaces, noiseless subsystems, and dynamical decoupling. It addresses…

Quantum Physics · Physics 2014-08-21 Daniel A. Lidar

An exactly solvable model for the decoherence of one and two-qubit states interacting with a spin-bath, in the presence of a time-dependent magnetic field is studied. The magnetic field is static along $\hat{z}$ direction and oscillatory in…

Quantum Physics · Physics 2011-06-10 D. D. Bhaktavatsala Rao

We review the problem of spin decoherence of magnetic atoms deposited on a surface. Recent breakthroughs in scanning tunnelling microscopy (STM) make it possible to probe the spin dynamics of individual atoms, either isolated or integrated…

Mesoscale and Nanoscale Physics · Physics 2017-02-14 F. Delgado , J. Fernández-Rossier

We introduce an exactly solvable model to study decoherence of a central spin interacting with a spin bath where the coupling is mediated by phonons which we assume to be in a coherent state or thermal distribution. For the coherent state…

Quantum Physics · Physics 2010-12-02 O. Bozat , Z. Gedik

The conditions under which an open quantum mechanical system may be described by mixed quantum-classical dynamics are investigated. Decoherence is studied using influence functional methods in a model composite quantum system comprising two…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Kazutomu Shiokawa , Raymond Kapral

We study the dynamics of a single spin-1/2 coupled to a bath of spins-1/2 by inhomogeneous Heisenberg couplings including a central magnetic field. This central-spin model describes decoherence in quantum bit systems. An exact formula for…

Statistical Mechanics · Physics 2009-11-11 Michael Bortz , Joachim Stolze

Decoherence of a central spin coupled to an interacting spin bath via inhomogeneous Heisenberg coupling is studied by two different approaches, namely an exact equations of motion (EOMs) method and a Chebyshev expansion technique (CET). By…

Mesoscale and Nanoscale Physics · Physics 2016-01-20 Ning Wu , Nina Fröhling , Xi Xing , Johannes Hackmann , Arun Nanduri , Frithjof B. Anders , Herschel Rabitz

The control of open quantum systems has a fundamental relevance for fields ranging from quantum information processing to nanotechnology. Typically, the system whose coherent dynamics one wants to manipulate, interacts with an environment…

Mesoscale and Nanoscale Physics · Physics 2007-06-20 Gonzalo A. Alvarez