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Related papers: The Structure of Decoherence-free Subsystems

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Quantum feedback is assuming increasingly important role in quantum control and quantum information processing. In this work we analyze the application of such feedback techniques in eliminating decoherence in open quantum systems. In order…

Quantum Physics · Physics 2016-11-15 Narayan Ganesan , Tzyh Jong Tarn

Engineered infrastructure systems pose inverse problems in which hidden states, unknown parameters, and subsystem couplings must be inferred from sparse and noisy measurements. These problems are difficult because physical subsystems are…

Systems and Control · Electrical Eng. & Systems 2026-05-28 Esmaeil Ghorbani , Jürgen Hackl

Artificial quantum systems with synthetic dimensions enable exploring novel quantum phenomena difficult to create in conventional materials. These synthetic degrees of freedom increase the system's dimensionality without altering its…

Quantum Physics · Physics 2025-08-11 Alexey Gorlach , Andrea Pizzi , Klaus Mølmer , Joseph Avron , Mordechai Segev , Ido Kaminer

We consider how randomness can be made to play a useful role in quantum information processing - in particular, for decoherence control and the implementation of quantum algorithms. For a two-level system in which the decoherence channel is…

Quantum Physics · Physics 2007-05-23 Chiu Fan Lee , Neil F. Johnson

We introduce a generalized theory of decoherence-free subspaces and subsystems (DFSs), which do not require accurate initialization. We derive a new set of conditions for the existence of DFSs within this generalized framework. By relaxing…

Quantum Physics · Physics 2007-05-23 A. Shabani , D. A. Lidar

An alternative approach to decoherence, named non-dynamical decoherence is developed and used to resolve the quantum measurement problem. According to decoherence, the observed system is open to a macroscopic apparatus(together with a…

Quantum Physics · Physics 2015-04-08 Yu-Lei Feng , Yi-Xin Chen

Coherent quantum phenomena can only emerge when decoherence is minimized, and mastery over decoherence is technologically crucial for designing and operating functional quantum devices. However, its microscopic mechanisms in…

Mesoscale and Nanoscale Physics · Physics 2026-04-01 Xian-Peng Zhang , Yan-Qing Feng , Haiwen Liu , Wanxiang Feng , Yugui Yao

A quantum system consisting of two subsystems is separable if its density matrix can be written as $\rho=\sum w_K \rho_K'\otimes \rho_K''$, where $\rho_K'$ and $\rho_K''$ are density matrices for the two subsytems, and the positive weights…

Quantum Physics · Physics 2007-05-23 Asher Peres

We show how to efficiently exploit decoherence free subspaces (DFSs), which are immune to collective noise, for realizing quantum repeaters with long lived quantum memories. Our setup consists of an assembly of simple modules and we show…

Quantum Physics · Physics 2007-05-23 Alexander Klein , Uwe Dorner , Carolina Moura Alves , Dieter Jaksch

A mesoscopic evolution equation for an ensemble of mesoparticles follows after the elimination of internal degrees of freedom. If the system is composed of a hierarchy of scales, the reduction procedure could be worked repeatedly and the…

Quantum Physics · Physics 2008-11-26 J. C. Flores

An algebraic formalism for quantum decoherence in systems with continuous evolution spectrum is introduced. A certain subalgebra, dense in the characteristic algebra of the system, is defined in such a way that Riemann-Lebesgue theorem can…

Mathematical Physics · Physics 2019-08-17 M. A. Castagnino , A. R. Ordoniez

Universal quantum computation on decoherence-free subspaces and subsystems (DFSs) is examined with particular emphasis on using only physically relevant interactions. A necessary and sufficient condition for the existence of…

Quantum Physics · Physics 2009-11-06 Julia Kempe , Dave Bacon , Daniel A. Lidar , K. Birgitta Whaley

Quantum coherence plays a fundamental and operational role in different areas of physics. A resource theory has been developed to characterize the coherence of distinguishable particles systems. Here we show that indistinguishability of…

The general aim of this paper is to supply a method to decide whether a discrete system decoheres or not, and under what conditions decoherence occurs, with no need of appealing to computer simulations to obtain the time evolution of the…

Quantum Physics · Physics 2011-06-14 Mario Castagnino , Sebastian Fortin

This paper studies the energy decoherence of an interacting quantum system. It first reviews the experiments that motivated the postulates of quantum mechanics. It then discusses a decoherence that occurs dynamically in a closed system.…

Quantum Physics · Physics 2024-12-03 Henry Crumley

Quantum technologies have shown immeasurable potential to effectively solve several information processing tasks such as prime number factorization, unstructured database search or complex macromolecule simulation. As a result of such…

Quantum Physics · Physics 2022-03-08 Josu Etxezarreta Martinez

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

We study an influence of the continuous measurement in a composite quantum system C on the evolution of the states of its parts. It is shown that the character of the evolution (decoherence or recoherence) depends on the type of the…

Quantum Physics · Physics 2009-11-11 E. D. Vol

Two-dimensional topological states of matter offer a route to quantum computation that would be topologically protected against the nemesis of the quantum circuit model: decoherence. Research groups in industry, government and academic…

Mathematical Physics · Physics 2016-05-04 Eric C. Rowell

We introduce a general operational characterization of information-preserving structures (IPS) -- encompassing noiseless subsystems, decoherence-free subspaces, pointer bases, and error-correcting codes -- by demonstrating that they are…

Quantum Physics · Physics 2009-11-13 Robin Blume-Kohout , Hui Khoon Ng , David Poulin , Lorenza Viola