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Related papers: Models of Short-Time Qubit Decoherence

200 papers

We present and discuss a general density-matrix description of energy-dissipation and decoherence phenomena in open quantum systems, able to overcome the intrinsic limitations of the conventional Markov approximation. In particular, the…

Quantum Physics · Physics 2015-05-30 Michele Pepe , David Taj , Rita Claudia Iotti , Fausto Rossi

We consider decoherence of quantum registers, which consist of the qubits sited approximately periodically in space. The sites of the qubits are permitted to have a small random variance. We derive the explicit conditions under which the…

Quantum Physics · Physics 2007-05-23 Lu-Ming Duan , Guang-Can Guo

The dynamics of simple qubit systems in a chain configuration coupled at both ends to separate bosonic baths at different temperatures is studied. An exact analytical solution of the master equation in the Born-Markov approximation for the…

Quantum Physics · Physics 2014-01-13 I. Sinayskiy , N. Pumulo , F. Petruccione

It is known that a quantum system with finite degrees of freedom can simulate a composite of a system and an environment if the state of the hypothetical environment is randomized by external manipulation. We show theoretically that any…

Quantum feedback can stabilize a two-level atom against decoherence (spontaneous emission), putting it into an arbitrary (specified) pure state. This requires perfect homodyne detection of the atomic emission, and instantaneous feedback.…

Quantum Physics · Physics 2009-11-06 Jin Wang , H. M. Wiseman , G. J. Milburn

We carry out a systematic analysis of a pair of coupled qubits, each of which is subject to its own dissipative environment, and argue that a combination of the inter-qubit couplings which provides for the lowest possible decoherence rates…

Strongly Correlated Electrons · Physics 2009-11-10 I. A. Grigorenko , D. V. Khveshchenko

Several applications of quantum machine learning (QML) rely on a quantum measurement followed by training algorithms using the measurement outcomes. However, recently developed QML models, such as variational quantum circuits (VQCs), can be…

Quantum Physics · Physics 2023-08-31 Hossein T. Dinani , Diego Tancara , Felipe F. Fanchini , Ariel Norambuena , Raul Coto

We develop a method to study quantum impurity models, small interacting quantum systems linearly coupled to an environment, in presence of an additional Markovian quantum bath, with a generic non-linear coupling to the impurity. We aim at…

Quantum Physics · Physics 2025-03-10 Orazio Scarlatella , Marco Schirò

We study and compare the decoherent histories approach, the environment-induced decoherence and the localization properties of thesolutions to the stochastic Schr\"{o}dinger equation in quantum jump simulationand quantum state diffusion…

General Relativity and Quantum Cosmology · Physics 2011-08-04 Ting Yu

We introduce new measures of decoherence appropriate for evaluation of quantum computing designs. Environment-induced deviation of a quantum system's evolution from controlled dynamics is quantified by a single numerical measure. This…

Mesoscale and Nanoscale Physics · Physics 2010-10-12 Leonid Fedichkin , Arkady Fedorov , Vladimir Privman

It is discussed the decoherence problems in ensemble large-scale solid state NMR quantum computer based on the array of P donor atoms having nuclear spin I = 1/2. It is considered here, as main mechanisms of decoherence for low temperature…

Quantum Physics · Physics 2009-11-07 A. A. Kokin

We show that the qubit decoherence due to zero-temperature energy relaxation can be almost completely suppressed by using the quantum uncollapsing procedure. To protect a qubit state, a partial quantum measurement moves it towards the…

Quantum Physics · Physics 2015-05-13 Alexander N. Korotkov , Kyle Keane

Physicists are attracted to open-system dynamics, how quantum systems evolve, and how they can protected from unnecessary environmental noise, especially environmental memory effects are not negligible, as with non-Markovian approximations.…

Quantum Physics · Physics 2021-06-02 Akbar Islam , An Min Wang , Ahmad Abliz

We study the behavior of non-Markovianity with respect to the localization of the initial environmental state. The "amount" of non-Markovianity is measured using divisibility and distinguishability as indicators, employing several schemes…

Quantum Physics · Physics 2018-01-03 David Davalos , Carlos Pineda

Enhancing the quantum correlations in realistic quantum systems interacting with the environment of finite temperature is an important subject in quantum information processing. In this paper, we use weak measurement and measurement…

Quantum Physics · Physics 2014-06-25 Nasibollah Doustimotlagh , Shuhao Wang , Chenglong You , Gui-Lu Long

Quantum metrology utilizes quantum effects to reach higher precision measurements of physical quantities compared with their classical counterparts. However the ubiquitous decoherence obstructs its application. Recently, non-Markovian…

Quantum Physics · Physics 2020-03-04 Kai Bai , Hong-Gang Luo , Wenxian Zhang , Meng Xiao

In the scale-up of quantum computers, the framework underpinning fault-tolerance generally relies on the strong assumption that environmental noise affecting qubit logic is uncorrelated (Markovian). However, as physical devices progress…

We have studied the decoherence properties of adiabatic quantum computation (AQC) in the presence of in general non-Markovian, e.g., low-frequency, noise. The developed description of the incoherent Landau-Zener transitions shows that the…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 M. H. S. Amin , Dmitri V. Averin , James A. Nesteroff

The conditions under which quantum-classical Liouville dynamics may be reduced to a master equation are investigated. Systems that can be partitioned into a quantum-classical subsystem interacting with a classical bath are considered.…

Statistical Mechanics · Physics 2015-06-25 Robbie Grunwald , Raymond Kapral

We briefly review the oscillator and spin bath models of quantum environments, which can be used to describe the low-energy dynamics of open quantum systems. We then use them to discuss both the mechanisms causing decoherence at low $T$,…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 M. Dube , P. C. E. Stamp