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Related papers: Decoherence and relaxation of a qubit coupled to a…

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Fast quantum oscillations of a charge qubit in a double quantum dot fabricated in a Si/SiGe heterostructure are demonstrated and characterized experimentally. The measured inhomogeneous dephasing time T2* ranges from 127ps to ~2.1ns; it…

Quantum information processing (QIP) requires thorough assessment of decoherence. Atoms or ions prepared for QIP often become addressed by radiation within schemes of alternating microwave-optical double resonance. A well-defined amount of…

Quantum Physics · Physics 2011-12-23 Chr. Balzer , Th. Hannemann , D. Reiß , W. Neuhauser , P. E. Toschek , Chr. Wunderlich

In this lectures, we have described some essential features of loss of coherence by a qubit coupled to the environment. We have first presented well known semiclassical arguments that relate both decoherence and relaxation to the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Alex Grishin , Igor V. Yurkevich , Igor V. Lerner

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

This Letter deals with the time evolution of a qubit weakly coupled to a reservoir which has a symmetry broken state with long range order at finite temperatures. In particular, we model the ordered reservoir by a standard BCS…

Mesoscale and Nanoscale Physics · Physics 2013-04-16 Juliana Restrepo , S. Camalet , R. Chitra

A master equation for the deformed quantum harmonic oscillator interacting with a dissipative environment, in particular with a thermal bath, is derived in the microscopic model by using perturbation theory, for the case when the…

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

The characterization and mitigation of decoherence in natural and artificial two-level systems (qubits) is fundamental to quantum information science and its applications. Decoherence of a quantum superposition state arises from the…

The effect of chaotic bath dynamics on the decoherence of a quantum system is examined for the vibrational degrees of freedom of a diatomic molecule in a realistic, constant temperature collisional bath. As an example, the specific case of…

Quantum Physics · Physics 2012-04-05 A. S. Sanz , Y. Elran , P. Brumer

The dissipative quantum dynamics of an anharmonic oscillator coupled to a bath is studied with the purpose of elucidating the differences between the relaxation to a spin bath and to a harmonic bath. Converged results are obtained for the…

Quantum Physics · Physics 2007-05-23 D. Gelman , C. P. Koch , R. Kosloff

We investigate a two-level spin system based anti-parity-time (anti-$\mathcal{PT}$)-symmetric qubit and study its decoherence as well as entanglement entropy properties. We compare our findings with that of the corresponding…

Quantum Physics · Physics 2020-08-12 Julia Cen , Avadh Saxena

Real quantum systems couple to their environment and lose their intrinsic quantum nature through the process known as decoherence. Here we present a method for minimizing decoherence by making it energetically unfavorable. We present a…

Quantum Physics · Physics 2009-11-06 D. Bacon , K. R. Brown , K. B. Whaley

We study the time evolution of a single qubit in contact with a bath, within the framework of projection operator methods. Employing the so-called modified Redfield theory which also treats energy conserving interactions non-perturbatively,…

Statistical Mechanics · Physics 2024-06-10 Jiaozi Wang , Jochen Gemmer

We study the self-contained three-qubit quantum refrigerator, with a three-body interaction enabling cooling of the target qubit, in presence of baths composed of anharmonic quantum oscillators with Kerr-type nonlinearity. We show that such…

Quantum Physics · Physics 2023-11-20 Tanaya Ray , Sayan Mondal , Aparajita Bhattacharyya , Ahana Ghoshal , Debraj Rakshit , Ujjwal Sen

In this work we study several models of decoherence and how different quantum maps and algorithms react when perturbed by them. Following closely Ref. [1], generalizations of the three paradigmatic one single qubit quantum channels (these…

Quantum Physics · Physics 2007-05-23 Mario Leandro Aolita , Marcos Saraceno

Markovian regime decoherence effects in quantum computers are studied in terms of the fidelity for the situation where the number of qubits N becomes large. A general expression giving the decoherence time scale in terms of Markovian…

Quantum Physics · Physics 2015-06-26 B J Dalton

We analyze two coupled quantum oscillators in a common Lorentzian environment and control them by detuning (temporarily shifting) their frequencies. The reduced dynamics are solved exactly, without Born or Markov approximations, by…

Quantum Physics · Physics 2026-01-30 Ali Abu-Nada , Lian-Ao Wu

We theoretically and numerically study the quantum dynamics of two degenerate optical parametric oscillators with mutual injections. The cavity mode in the optical coupling path between the two oscillator facets is explicitly considered.…

Quantum Physics · Physics 2015-11-03 Kenta Takata , Alireza Marandi , Yoshihisa Yamamoto

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

We investigate the effects of the initial correlation on the dynamics of open system in the exactly solvable pure dephasing model. We show that the role of the initial correlation come into play through a phase function and a weight factor,…

Quantum Physics · Physics 2015-06-11 Yang Gao

We study the resilience of the surface code to decoherence caused by the presence of a bosonic bath. This approach allows us to go beyond the standard stochastic error model commonly used to quantify decoherence and error threshold…

Quantum Physics · Physics 2013-08-02 P. Jouzdani , E. Novais , E. R. Mucciolo