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Related papers: Coherence transformations in single qubit systems

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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

We investigate manipulations of pure quantum states under incoherent or strictly incoherent operations assisted by a coherence battery, that is, a storage device whose degree of coherence is allowed to fluctuate in the process. This leads…

Quantum Physics · Physics 2018-09-26 Benjamin Morris , Gerardo Adesso

The efficient single photon emission capabilities of quantum dot molecules position them as promising platforms for quantum information processing. Furthermore, quantum dot molecules feature a "decoherence-free" subspace that enables spin…

Quantum Physics · Physics 2021-03-31 D. Farfurnik , R. M. Pettit , Z. Luo , E. Waks

Random permutation circuits were recently introduced as minimal models for local many-body dynamics that can be interpreted both as classical and quantum. Standard dynamical complexity indicators such as damage spreading and…

Statistical Mechanics · Physics 2026-03-17 Bruno Bertini , Katja Klobas , Pavel Kos , Daniel Malz

How quantum coherence influences thermodynamic behavior remains an open question in quantum thermodynamics. Here we investigate this relation within the pure dephasing framework, where a central qubit interacts with a finite Ising-like spin…

Quantum Physics · Physics 2026-03-31 Marino P. Lenzarini , Diogo O. Soares-Pinto

Protecting the dynamics of coupled quantum systems from decoherence by the environment is a key challenge for solid-state quantum information processing. An idle qubit can be efficiently insulated from the outside world via dynamical…

Mesoscale and Nanoscale Physics · Physics 2012-05-01 T. van der Sar , Z. H. Wang , M. S. Blok , H. Bernien , T. H. Taminiau , D. M. Toyli , D. A. Lidar , D. D. Awschalom , R. Hanson , V. V. Dobrovitski

It is known that it is possible to encode a logical qubit over many physical qubits such that it is immune to the effects of collective decoherence, and it is possible to perform universal quantum computation using these `decoherence-free'…

Quantum Physics · Physics 2013-10-30 Bobby Antonio , Sougato Bose

We develop a hybrid oscillator-qubit processor framework for quantum simulation of strongly correlated fermions and bosons that avoids the boson-to-qubit mapping overhead encountered in qubit hardware. This framework gives exact…

Exchange-only (EO) spin qubits in quantum dots offer an expansive design landscape for architecting scalable device layouts. The study of two-EO-qubit operations, which involve six electrons in six quantum dots, has so far been limited to a…

We analyze the optically driven dynamics of a qubit implemented on a singlet-triplet subspace of two-electron states in a self-assembled quantum dot molecule. We study two possible control schemes based on the coupling to an excited…

Mesoscale and Nanoscale Physics · Physics 2023-05-05 Karol Kawa , Tilmann Kuhn , Paweł Machnikowski

For many implementations of quantum computing, 1/f and other types of broad-spectrum noise are an important source of decoherence. An important step forward would be the ability to back out the characteristics of this noise from qubit…

Quantum Physics · Physics 2011-07-15 Robert Joynt , Dong Zhou , Qiang-Hua Wang

Quantum coherence, a basic feature of quantum mechanics residing in superpositions of quantum states, is a resource for quantum information processing. Coherence emerges in a fundamentally different way for nonidentical and identical…

Decoherence is the main obstacle to quantum computation. The decoherence rate per qubit is typically assumed to be constant. It is known, however, that quantum registers coupling to a single reservoir can show a decoherence rate per qubit…

Quantum Physics · Physics 2020-05-20 Joris Kattemölle , Jasper van Wezel

We investigate the spatio-temporal dynamics of coupled chaotic systems with nonlocal interactions, where each element is coupled to its nearest neighbors within a finite range. Depending upon the coupling strength and coupling radius, we…

Quantum coherence offers potential for energy conversion technologies. It influences light absorption and emission, affecting energy conversion limits and efficiency. As a result, quantum coherence is being harnessed to boost performance in…

Quantum Physics · Physics 2026-02-13 Ludovica Donati , Francesco Saverio Cataliotti , Stefano Gherardini

We introduce a procedure based on quantum expectation values of measurement observables to characterize quantum coherence. Our measure allows one to quantify coherence without having to perform tomography of the quantum state, and can be…

Quantum noise is ubiquitous to quantum systems as they incessantly interact with their surroundings and results in degrading useful resources such as coherence for single quantum systems and quantum correlations for multipartite systems.…

Quantum Physics · Physics 2016-11-30 Kaifeng Bu , Swati , Uttam Singh , Junde Wu

A set of new schemes for quantum computation and communication have been either designed or experimentally realized using optimal quantum resources. A multi-output quantum teleportation scheme, where a sender (Alice) teleports an m and…

Quantum Physics · Physics 2025-07-15 Satish Kumar

In this paper, we analyze the evolution of quantum coherence in a two-qubit system going through the amplitude damping channel. After they have gone through this channel many times, we analyze the systems with respect to the coherence of…

Quantum Physics · Physics 2017-12-29 Ming-Jing Zhao , Teng Ma , YuQuan Ma

We study a decoherence reduction scheme that involves an intermediate measurement on the qubit in an equal superposition basis, in the general framework of all qubit-environment interactions that lead to qubit pure decoherence. We show…

Quantum Physics · Physics 2024-02-22 Bartosz Rzepkowski , Katarzyna Roszak