English
Related papers

Related papers: Importance of bath dynamics for decoherence in spi…

200 papers

An exact reduced dynamical map along with its operator sum representation is derived for a central spin interacting with a thermal spin environment. The dynamics of the central spin shows high sustainability of quantum traits such as…

Quantum Physics · Physics 2017-11-23 Chiranjib Mukhopadhyay , Samyadeb Bhattacharya , Avijit Misra , Arun Kumar Pati

The interaction between a central qubit spin and a surrounding bath of spins is critical to spin-based solid state quantum sensing and quantum information processing. Spin-bath interactions are typically strongly anisotropic, and rapid…

A suitable sequence of sharp pulses applied to a spin coupled to a bosonic bath can cool its state, i.e., increase its polarization or ground state occupation probability. Starting from an unpolarized state of the spin in equilibrium with…

Quantum Physics · Physics 2009-11-10 A. E. Allahverdyan , R. Serral Gracia , Th. M. Nieuwenhuizen

We solve the long-standing central spin problem for a general set of inhomogeneous bath couplings and a large class of initial bath states. We compute the time evolution of the coherence of a central spin coupled to a spin bath by resumming…

Mesoscale and Nanoscale Physics · Physics 2012-10-09 Edwin Barnes , Łukasz Cywiński , S. Das Sarma

Certain issues regarding the time-scales over which environment-induced decoherence occurs, and the nature of emergent pointer states, are discussed. A model system, namely, a Stern-Gerlach setup coupled to a quantum mechanical "heat-bath"…

Quantum Physics · Physics 2012-01-10 Tabish Qureshi

We study the dynamical stability of the entanglement between the two spin ensembles in the presence of an environment. For a comparative study, we consider the two cases: a single spin ensemble, and two ensembles linearly coupled to a bath,…

Quantum Physics · Physics 2015-05-13 H. T. Ng , S. Bose

We study two anisotropically interacting spins coupled to optical phonons; we restrict our analysis to the regime of strong coupling to the environment, to the antiadiabatic region, and to the subspace with zero value for $S^z_T$ (the…

Strongly Correlated Electrons · Physics 2015-06-17 Amit Dey , Sudhakar Yarlagadda

Decoherence of a quantum state coupled to an exterior environment is at the foundation of our understanding of the emergence of classical behavior from the quantum world, but how does it emerge in a finite closed quantum system? Here this…

Quantum Physics · Physics 2015-06-16 O. Fialko

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

Effective descriptions accounting for the evolution of quantum systems that are acted on by a bath are desirable. As the number of bath degrees of freedom increases and full quantum simulations turn out computationally prohibitive, simpler…

Quantum Physics · Physics 2014-02-18 A. S. Sanz

A complete treatment of the entanglement of two-level systems, which evolves through the contact with a thermal bath, must include the fact that the system and the bath are not fully separable. Therefore, quantum coherent superpositions of…

Quantum Physics · Physics 2015-05-18 Arend G. Dijkstra , Yoshitaka Tanimura

The spin-boson model is a paradigm for studying decoherence, relaxation, entanglement and other effects that arise in a quantum system coupled to environmental degrees of freedom. At zero temperature, a localization-delocalization phase…

Quantum Physics · Physics 2015-01-22 Yao Yao , Nengji Zhou , Javier Prior , Yang Zhao

In many realizations of electron spin qubits the dominant source of decoherence is the fluctuating nuclear spin bath of the host material. The slowness of this bath lends itself to a promising mitigation strategy where the nuclear spin bath…

Mesoscale and Nanoscale Physics · Physics 2010-11-30 Hendrik Bluhm , Sandra Foletti , Diana Mahalu , Vladimir Umansky , Amir Yacoby

We show that the coherence of an electron spin interacting with a bath of nuclear spins can exhibit a well-defined purely exponential decay for special (`narrowed') bath initial conditions in the presence of a strong applied magnetic field.…

Mesoscale and Nanoscale Physics · Physics 2008-04-07 W. A. Coish , Jan Fischer , Daniel Loss

In the framework of nuclear magnetic resonance, we consider the general problem of the coherent control of a spin coupled to a bath by means of composite or continuous pulses of duration $\tau_\mathrm{p}$. We show explicity that it is…

Quantum Physics · Physics 2010-03-16 S. Pasini , P. Karbach , C. Raas , G. S. Uhrig

We experimentally demonstrate that the decoherence of a spin by a spin bath can be completely eliminated by fully polarizing the spin bath. We use electron paramagnetic resonance at 240 gigahertz and 8 Tesla to study the spin coherence time…

Quantum Physics · Physics 2009-11-13 Susumu Takahashi , Ronald Hanson , Johan van Tol , Mark S. Sherwin , David D. Awschalom

We study a model of dephasing (decoherence) in a two-state quantum system (qubit) coupled to a bath of harmonic oscillators. An exact analytic solution for the reduced dynamics of a two-state system in this model has been obtained…

Quantum Physics · Physics 2015-05-28 V. G. Morozov , S. Mathey , G. Röpke

The study of the decoherence of qubits in spin systems is almost restricted to environments whose constituents are spin-$\frac{1}{2}$ particles. In this paper we consider environments that are composed of particles of higher spin, and we…

Quantum Physics · Physics 2022-07-08 Yamen Hamdouni

A model of an arbitrary spin coupled to a bath of spins 1/2 in a star configuration is considered. The exact reduced dynamics of the central spin is found for the case of non-correlated initial conditions of the system and the bath. The…

Quantum Physics · Physics 2014-06-20 V. Semin , I. Sinayskiy , F. Petruccione

We study the dynamics of a quantum spin ensemble controlled by trains of ultrashort pulses. To model disturbances of the kicks, we consider that the spins are submitted to different kick trains which follow regular, random, stochastic or…

Quantum Physics · Physics 2013-06-10 David Viennot , Lucile Aubourg