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Related papers: The decoherence of coupled spin qubits system

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We extend study of the Jaynes-Cummings model involving a pair of identical two-level atoms (or qubits) interacting with a single mode quantized field. We investigate the effects of replacing the radiation field mode with a composite spin,…

Quantum Physics · Physics 2017-07-26 Iskandar Bahari , Timothy P. Spiller , Shane Dooley , Anthony Hayes , Francis McCrossan

Decoherence of a quantum system arising from its interaction with an environment is a key concept for understanding the transition between the quantum and classical world as well as performance limitations in quantum technology…

Molecular nanomagnets are quantum spin systems potentially serving as qudits for future quantum technologies thanks to their many accessible low-energy states. At low temperatures, the primary source of error in these systems is pure…

We study the properties of spectra and eigenfunctions for a chain of $1/2- $spins (qubits) in an external time-dependent magnetic field, and under the conditions of non-selective excitation (when the amplitude of the magnetic field is…

Quantum Physics · Physics 2009-11-07 G. P. Berman , F. Borgonovi , F. M. Izrailev , V. I. Tsifrinovich

We study systematically the non-Markovian decoherence dynamics of a dissipative two-level system, i.e., the so-called spin-boson model. It is interesting to find that the decoherence tends to be inhibited with the increase of the coupling…

Quantum Physics · Physics 2013-06-04 Hai-Bin Liu , Jun-Hong An , Chong Chen , Qing-Jun Tong , Hong-Gang Luo , C. H. Oh

We propose and solve a simple but very general quantum model of an SU(2) spin interacting with a large external system with N states. The coupling is described by a random hamiltonian in a new general gaussian SU(2)xU(N) random matrix…

Mathematical Physics · Physics 2011-01-13 Francois David

We study the decoherence induced by the environment over a composite quantum system, comprising two coupled subsystems A and B, which may be a harmonic or an upside-down oscillators. We analyze the case in which the B-subsystem is in direct…

Quantum Physics · Physics 2009-11-11 Fernando C. Lombardo , Paula I. Villar

We study the decoherence of two coupled spins that interact with a spin-bath environment. It is shown that the connectivity and the coupling strength between the spins in the environment are of crucial importance for the decoherence of the…

Quantum Physics · Physics 2008-10-22 Shengjun Yuan , Mikhail I. Katsnelson , Hans De Raedt

We examine the influence of environmental interactions on simple quantum systems by obtaining the exact reduced dynamics of a qubit coupled to a one-dimensional spin bath. In contrast to previous studies, both the qubit-bath coupling and…

Quantum Physics · Physics 2014-06-17 Ning Wu , Arun Nanduri , Herschel Rabitz

We demonstrate by an explicit model calculation that the decay of entanglement of two two-state systems (two qubits) is governed by the product of the factors that measure the degree of decoherence of each of the qubits, subject to…

Quantum Physics · Physics 2010-10-12 D. Tolkunov , V. Privman , P. K. Aravind

A high degree of quantum coherence is a crucial requirement for the implementation of quantum logic devices. Solid state nanodevices seem particularly promising from the point of view of integrability and flexibility in the design. However…

Superconductivity · Physics 2007-05-23 G. Falci , E. Paladino , R. Fazio

Decoherence of a shallow donor electron spin in silicon caused by electron-lattice interaction is studied. We find that there are two time scales associated with the evolution of the electron spin density matrix: the fast but incomplete…

Condensed Matter · Physics 2009-11-07 D. Mozyrsky , Sh. Kogan , G. P. Berman

We discuss the notion of quantum mechanical coherence in its connection with time evolution and stationarity. The transition from coherence to decoherence is examined in terms of an equation for the time dependence of the density matrix. It…

Quantum Physics · Physics 2007-05-23 L. Stodolsky

In this work, two experimentally feasible methods of decoherence engineering-one based on the application of stochastic classical kicks and the other based on temporally randomized pulse sequences are combined. A different coupling…

Quantum Physics · Physics 2016-02-10 Govind Unnikrishnan

The usefulness of solid-state spins in quantum technologies depends on how long they can remain in a coherent superposition of quantum states. This Colloquium discusses how first-principles simulations can predict spin dynamics for…

Quantum Physics · Physics 2025-03-21 Mykyta Onizhuk , Giulia Galli

In Si/SiGe quantum dots, the decoherence behavior of spin qubits usually comes from the non-Markovian effect of the charge noise. To improve the performance of using the coherent noise models in the decoherence simulation and tomography…

Quantum Physics · Physics 2025-10-28 Wei-en Chiu , Chia-Hsien Huang , Yi-Hsien Wu , Hsi-Sheng Goan

On the way to solid-state quantum computing, overcoming decoherence is the central issue. In this contribution, we discuss the modeling of decoherence of a superonducting flux qubit coupled to dissipative electronic circuitry. We discuss…

Superconductivity · Physics 2015-06-24 F. K. Wilhelm , M. J. Storcz , C. H. van der Wal , C. J. P. M. Harmans , J. E. Mooij

We study decoherence produced by a discrete environment on a charge Josephson qubit by introducing a model of an environment of bistable fluctuators. In particular we address the effect of $1/f$ noise where memory effects play an important…

Superconductivity · Physics 2015-06-24 E. Paladino , L. Faoro , G. Falci

The effects of fluctuating boundaries on a superposition state of a quantum particle in a box is studied. We consider a model in one space dimension in which the initial state is a coherent superposition of two energy eigenstates. The…

Quantum Physics · Physics 2012-05-11 V. A. De Lorenci , L. H. Ford

We analyze the entanglement properties of spins (qubits) close to the boundary of spin chains in the vicinity of a quantum critical point and show that the concurrence at the boundary is significantly different from the one of bulk spins.…

Mesoscale and Nanoscale Physics · Physics 2009-07-23 T. Stauber , F. Guinea