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Related papers: Decoherence induced continuous pointer states

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We study the decoherence and the relaxation dynamics of topological states in an extended class of quantum Ising chains which can present a manyfold ground state subspace. The leading interaction of the spins with the environment is assumed…

Strongly Correlated Electrons · Physics 2019-03-27 Hannes Weisbrich , Wolfgang Belzig , Gianluca Rastelli

We study the effect of phonons on a proposed scheme for the direct measurement of two-electron spin states in a double quantum dot by monitoring the the noise of the current flowing through a quantum point contact coupled to one of the…

Quantum Physics · Physics 2015-04-01 Katarzyna Roszak , Łukasz Marcinowski , Paweł Machnikowski

In this work, we study and evaluate the impact of a periodic spin-lattice coupling in an Ising-like system on a 2D triangular lattice. Our proposed simple Hamiltonian considers this additional interaction as an effect of preferential phonon…

Statistical Mechanics · Physics 2024-01-30 R. M. L. Nascimento , Claudio J. DaSilva , L. S. Ferreira , A. A. Caparica

We study the decoherence of a qubit weakly coupled to frustrated spin baths. We focus on spin-baths described by the classical Ising spin glass and the quantum random transverse Ising model which are known to have complex thermodynamic…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 E. A. Winograd , M. J. Rozenberg , R. Chitra

We demonstrate how the presence of continuous weak symmetry can be used to analytically diagonalize the Liouvillian of a class Markovian dissipative systems with arbitrary strong interactions or nonlinearity. This enables an exact…

Quantum Physics · Physics 2022-02-21 Alexander McDonald , Aashish A. Clerk

Entanglement plays a crucial role in proposals for quantum metrology, yet demonstrating quantum enhancement in sensing with sustained spin entanglement remains a challenging endeavor. Here, we combine optical pumping and continuous quantum…

Quantum Physics · Physics 2025-04-09 Junlei Duan , Zhiwei Hu , Xingda Lu , Liantuan Xiao , Suotang Jia , Klaus Mølmer , Yanhong Xiao

The concept of entanglement entropy appears in multiple contexts, from black hole physics to quantum information theory, where it measures the entanglement of quantum states. We investigate the entanglement entropy in a simple model, the…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Karyn Le Hur

In this note we study a class of one-dimensional Ising chain having a highly degenerated set of ground-state configurations. The model consists of spin chain having infinite-range pair interactions with a given structure. We show that the…

Mathematical Physics · Physics 2017-01-19 L. A. Corona , R. Salgado-Garcia

We study the decoherence of a spin-1/2 induced by an environment which is on the verge of a continuous phase transition. We consider spin environments described by the ferromagnetic and antiferromagnetic Heisenberg models on a square…

Mesoscale and Nanoscale Physics · Physics 2007-06-15 S. Camalet R. Chitra

We compute numerically the second and third order nonlinear magnetic susceptibilities of an Ising ladder model in the context of two-dimensional coherent spectroscopy by using the infinite time-evolving block decimation method. The Ising…

Strongly Correlated Electrons · Physics 2023-04-26 Qi Gao , Yang Liu , Haijun Liao , Yuan Wan

We study a class of quantum measurement models. A microscopic object is entangled with a macroscopic pointer such that a distinct pointer position is tied to each eigenvalue of the measured object observable. Those different pointer…

Quantum Physics · Physics 2008-01-29 D. Spehner , F. Haake

We present a new short-time approximation scheme for evaluation of decoherence. At low temperatures, the approximation is argued to apply at intermediate times as well. It then provides a tractable approach complementary to Markovian-type…

Quantum Physics · Physics 2010-10-12 Vladimir Privman

In this report, we examine the decoherence of a spin qubits system coupled to counted spin chain with a $1/r^2$ interaction by using influence functional. We also examine the time evolution of density matrix numerically when environment is…

Mesoscale and Nanoscale Physics · Physics 2008-12-20 Toshifumi Itakura

The aim of this review is to show how ``ferromagnetic'' states, that is, states having a fully polarization, can produce intrinsic decoherence by unitary evolution. This effect can give an understanding of recent experiments on mesoscopic…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Marco Frasca

We study the dynamics of a symmetric two-level system strongly coupled to a broadened harmonic mode. Upon mapping the problem onto a spin-boson model with peaked spectral density, we show how analytic solutions can be obtained, at arbitrary…

Statistical Mechanics · Physics 2009-11-13 F. Nesi , M. Grifoni , E. Paladino

Quantum simulation of spin models can provide insight into complex problems that are difficult or impossible to study with classical computers. Trapped ions are an established platform for quantum simulation, but only systems with fewer…

We develop and implement a method for modeling decoherence processes on an N-dimensional quantum system that requires only an $N^2$-dimensional quantum environment and random classical fields. This model offers the advantage that it may be…

Quantum Physics · Physics 2009-11-10 G. Teklemariam , E. M. Fortunato , C. C. Lopez , J. Emerson , J. P. Paz , T. F. Havel , D. G. Cory

We propose a quantum optical implementation of a class of dissipative spin systems, including the XXZ and Ising model, with ultra-cold atoms in optical lattices. Employing the motional degree of freedom of the atoms and detuned Raman…

Quantum Physics · Physics 2013-02-18 Heike Schwager , J. Ignacio Cirac , Géza Giedke

We compare approaches to evaluation of decoherence at low temperatures in two-state quantum systems weakly coupled to the environment. By analyzing an exactly solvable model, we demonstrate that a non-Markovian approximation scheme yields…

Mesoscale and Nanoscale Physics · Physics 2010-10-12 Dmitry Solenov , Vladimir Privman

We investigate the infinite volume limit of quantized photon fields in multimode coherent states. We show that for states containing a continuum of coherent modes, it is mathematically and physically natural to consider their phases to be…

Mathematical Physics · Physics 2016-05-04 Alain Joye , Marco Merkli