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Related papers: Decoherence in a $\mathcal{PT}$-symmetric qubit

200 papers

Interaction of solid state qubits with environmental degrees of freedom strongly affects the qubit dynamics, and leads to decoherence. In quantum information processing with solid state qubits, decoherence significantly limits the…

Mesoscale and Nanoscale Physics · Physics 2010-02-26 Luca Chirolli , Guido Burkard

We show that the low-frequency modes of a sub-Ohmic bosonic heat bath generate an effective dynamical asymmetry for an intrinsically symmetric quantum spin -1/2. An initially fully polarized spin first decays towards a quasiequilibrium…

Statistical Mechanics · Physics 2015-03-13 P. Nalbach , M. Thorwart

We study the dynamics of a two-level impurity embedded in a two-dimensional Bose-Hubbard model at zero temperature from an open quantum system perspective. Results for the decoherence across the whole phase diagram are presented, with a…

Quantum Physics · Physics 2021-01-29 Fabio Caleffi , Massimo Capone , Inés de Vega , Alessio Recati

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

Decoherence of a localized electron spin in a solid state material (the ``central spin'' problem) at low temperature is believed to be dominated by interactions with nuclear spins in the lattice. This decoherence is partially suppressed…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 W. M. Witzel , S. Das Sarma

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

We introduce a general framework for realizing $\mathcal{PT}$-like phase transitions in non-Hermitian systems without imposing explicit parity--time ($\mathcal{PT}$) symmetry. The approach is based on constructing a Hamiltonian as the…

Optics · Physics 2025-11-18 Jacob L. Barnett , Ramy El-Ganainy

The interaction between solid-state qubits and their environmental degrees of freedom produces non-unitary effects like decoherence and dissipation. Uncontrolled decoherence is one of the main obstacles that must be overcome in quantum…

Quantum Physics · Physics 2014-11-24 Paula I. Villar , Fernando C. Lombardo

A qubit (containing two quantum states, 1 and 2), is coupled to a control register (state 3), which is subject to telegraph noise. We study the time evolution of the density matrix $\rho$ of an electron which starts in some coherent state…

Mesoscale and Nanoscale Physics · Physics 2009-09-01 Amnon Aharony , Ora Entin-Wohlman , Sushanta Dattagupta

We consider the $\mathcal{PT}$-symmetric quantum field theory on the noncommutative spacetime with angular twist and construct its pseudo-Hermitian interpretation. We explore the differences between internal and spatial parities in the…

High Energy Physics - Theory · Physics 2019-10-25 Oleg O. Novikov

This paper investigates the thermodynamics of a large class of non-Hermitian, $PT$-symmetric oscillators, whose energy spectrum is entirely real. The spectrum is estimated by second-order WKB approximation, which turns out to be very…

Quantum Physics · Physics 2014-11-18 H. F. Jones , E. S. Moreira

We present a rigorous analysis of the phenomenon of decoherence for general $N-$level systems coupled to reservoirs. The latter are described by free massless bosonic fields. We apply our general results to the specific cases of the qubit…

Quantum Physics · Physics 2009-11-13 M. Merkli , I. M. Sigal , G. P. Berman

The spin-boson (SB) model is a standard prototype for quantum dissipation, which we generalize in this work, to explore the dissipative effects on a one-dimensional spin-orbit (SO) coupled particle in the presence of a sub-ohmic bath. We…

Statistical Mechanics · Physics 2026-02-02 Sudip Sinha , Subhasis Sinha , Sushanta Dattagupta

Dephasing decoherence induced by interaction of one qubit with a quantum bath can be simulated classically by random unitary evolution without the need for a bath and this random unitary evolution is equivalent to the quantum case. For a…

Quantum Physics · Physics 2014-05-07 Daniel Crow , Robert Joynt

By using the Redfield form of the master equation, we investigate the decoherence times of a double quantum dot charge qubit (DQDCQ) in three different cases, namely when it is coupled to (I) the piezoelectric coupling phonon bath (PCPB),…

Quantum Physics · Physics 2010-01-28 Zeng-Zhao Li , Xiao-Yin Pan , Xian-Ting Liang

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

We make a novel observation about the decoherence phenomenon of the fermion in the Witten's supersymmetric (SUSY) quantum mechanical model. It is shown that, when the bosonic partner in the SUNY model is unobservable in a certain energy…

Quantum Physics · Physics 2007-05-23 T. Shi , Z. Song , C. P. Sun

Decoherence is the major stumbling block in the realization of a large-scale quantum computer. Ingenious methods have been devised to overcome decoherence, but their success has been proven only for over-simplified models of…

Quantum Physics · Physics 2009-11-13 Andrew P. Hines , P. C. E. Stamp

Dephasing in quantum systems is typically the result of its interaction with environmental degrees of freedom. We investigate within a spin-boson model the influence of a super-Ohmic environment on the dynamics of a quantum two-state…

Quantum Physics · Physics 2023-07-12 Philipp Nacke , Florian Otterpohl , Michael Thorwart , Peter Nalbach

We propose a novel symmetrization procedure to beat decoherence for oscillator-assisted quantum gate operations. The enacted symmetry is related to the global geometric features of qubits transformation based on ancillary oscillator modes,…

Quantum Physics · Physics 2009-11-10 Li-Xiang Cen , Paolo Zanardi