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Related papers: One, Two, and $n$ Qubit Decoherence

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Exploring an analytical expression for the convex roof of the pure state squared concurrence for rank 2 mixed states the entanglement of a system of three particles under decoherence is studied, using the monogamy inequality for mixed…

Quantum Physics · Physics 2009-08-28 Thiago R. de Oliveira

We study the problem of driving an unknown initial mixed quantum state onto a known pure state without using unitary transformations. This can be achieved, in an efficient manner, with the help of sequential measurements on at least two…

Quantum Physics · Physics 2009-11-11 L. Roa , G. Olivares

We review recent studies on the measures of zero temperature quantum correlations namely, the quantum entanglement (concurrence) and discord present in the final state of a transverse XY spin chain following a quench through quantum…

Quantum Physics · Physics 2015-06-05 Tanay Nag , Amit Dutta , Ayoti Patra

Quantum entanglement manifests as a distinctive correlation between particles that transcends classical boundaries when their quantum states cannot be described independently. On the other hand, as quantum systems interact with their…

Quantum Physics · Physics 2025-08-21 Samuel Marquez Gonzalez

We compare decoherence induced in a simple quantum system (qubit) for two different initial states of the environment: canonical (fixed temperature) and microcanonical (fixed energy), for the general case of a fully interacting oscillator…

Quantum Physics · Physics 2009-11-07 S. Khlebnikov , G. Sadiek

Certain physical aspects of quantum error correction are discussed for a quantum computer (n-qubit register) in contact with a decohering environment. Under rather plausible assumptions upon the form of the computer-environment interaction,…

Quantum Physics · Physics 2008-02-03 M. Biskup , P. Cejnar , R. Kotecky

We show that it is possible to explain the quantum measurement process within the framework of quantum mechanics without any additional postulates. The key concept of the theory is decoherence, which appears as an inherent characteristic of…

General Physics · Physics 2019-11-01 Riuji Mochizuki

We investigate decoherence in quantum systems coupled via dephasing-type interactions to an arbitrary environment with chaotic underlying classical dynamics. The coherences of the reduced state of the central system written in the…

Quantum Physics · Physics 2011-08-22 Gabriela Barreto Lemos , Fabricio Toscano

We study a pair of capacitively coupled singlet-triplet spin qubits. We characterize the two-qubit decoherence through two complementary measures, the decay time of coupled-qubit oscillations and the fidelity of entangled state preparation.…

Mesoscale and Nanoscale Physics · Physics 2017-10-11 Yang-Le Wu , S. Das Sarma

Controlable strong interaction of the qubit's bath with an external system (i.e. with the bath's environment) allows for choosing the conditions under which the decoherence of the qubit's states can be substantially decreased (in a certain…

Quantum Physics · Physics 2012-03-01 Miroljub Dugić

Decoherence originates from the leakage of quantum information into external degrees of freedom. For a qubit the two main decoherence channels are relaxation and dephasing. Here, we report an experiment on a superconducting qubit where we…

Quantum Physics · Physics 2018-07-16 Q. Ficheux , S. Jezouin , Z. Leghtas , B. Huard

Due to the rapid development of research in the field of quantum physics and quantum information over the past decades, the need to study physical models that can effectively implement quantum computing has increased. An integral part of…

Quantum Physics · Physics 2026-05-29 A. I. Smetana , A. R. Kuzmak

If a quantum system A, which is initially correlated to another system, E, undergoes an evolution separated from E, then the correlation to E generally decreases. Here, we study the conditions under which the correlation disappears (almost)…

Quantum Physics · Physics 2014-05-14 Frédéric Dupuis , Mario Berta , Jürg Wullschleger , Renato Renner

Decoherence in quantum bit circuits is presently a major limitation to their use for quantum computing purposes. We present experiments, inspired from NMR, that characterise decoherence in a particular superconducting quantum bit circuit,…

Superconductivity · Physics 2015-06-25 G. Ithier , E. Collin , P. Joyez , P. J. Meeson , D. Vion , D. Esteve , F. Chiarello , A. Shnirman , Y. Makhlin , J. Schriefl , G. Schon

We illustrate through numerical results a number of features of environment-induced decoherence under a broad class of apparatus-environment interactions in quantum measurements wherein the reduced system-apparatus density matrix evolves…

Quantum Physics · Physics 2007-06-13 Avijit Lahiri

We study the decoherence of a qubit weakly coupled to frustrated spin baths. We focus on spin-baths described by the classical Ising spin glass and the quantum random transverse Ising model which are known to have complex thermodynamic…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 E. A. Winograd , M. J. Rozenberg , R. Chitra

We study pure phase damping of two qubits due to fluctuating fields. As frequently employed, decoherence is thus described in terms of random unitary (RU) dynamics, i.e., a convex mixture of unitary transformations. Based on a separation of…

Quantum Physics · Physics 2010-12-22 Julius Helm , Walter T. Strunz

We study the entanglement dynamics and relaxation properties of a system of two interacting qubits in the two cases (I) two independent bosonic baths and (II) one common bath, at temperature T. The entanglement dynamics is studied in terms…

Quantum Physics · Physics 2017-05-10 G. Campagnano , A. Hamma , U. Weiss

The dynamics and decoherence of an electronic spin-1/2 qubit coupled to a bath of nuclear spins via hyperfine interactions in a quantum dot is studied. We show how exact results from the integrable solution can be used to understand the…

Strongly Correlated Electrons · Physics 2010-10-22 Michael Bortz , Sebastian Eggert , Christian Schneider , Robert Stubner , Joachim Stolze

Decoherence is the process by which quantum systems interact and become correlated with their external environments; quantum trajectories are a powerful technique by which decohering systems can be resolved into stochastic evolutions,…

Quantum Physics · Physics 2018-03-28 Todd A. Brun