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Related papers: Quantum Fourier Transform in a Decoherence-Free Su…

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We consider interactions that generate a universal set of quantum gates on logical qubits encoded in a collective-dephasing-free subspace, and discuss their implementations with trapped ions. This allows for the removal of the by-far…

Quantum Physics · Physics 2016-08-14 Leandro Aolita , Luiz Davidovich , Kihwan Kim , Hartmut Häffner

We investigate the extent to which ``interaction-free'' measurements perturb the state of quantum systems. We show that the absence of energy exchange during the measurement is not a sufficient criterion to preserve that state, as the…

Quantum Physics · Physics 2009-11-06 S. Potting , E. S. Lee , W. Schmitt , I. Rumyantsev , B. Mohring , P. Meystre

In this contribution I give a brief introduction to the essential concepts and mechanisms of decoherence by the environment. The emphasis will be not so much on technical details but rather on conceptual issues and the impact on the…

Quantum Physics · Physics 2007-05-23 Erich Joos

Large scale quantum information processing requires stable and long-lived quantum memories. Here, using atom-photon entanglement, we propose an experimentally feasible scheme to realize decoherence-free quantum memory with atomic ensembles,…

Quantum Physics · Physics 2008-11-05 Feng Mei , Ya-Fei Yu , Zhi-Ming Zhang

Demonstrating quantum advantage has been a pressing challenge in the field. Most claimed quantum speedups rely on a subroutine in which classical information can be accessed in a coherent quantum manner, which imposes a crucial constraint…

Quantum Physics · Physics 2025-11-04 Nhat A. Nghiem

A Quantum Computer is a new type of computer which can solve problems such as factoring and database search very efficiently. The usefulness of a quantum computer is limited by the effect of two different types of errors, decoherence and…

Quantum Physics · Physics 2007-05-23 Kevin M. Obenland , Alvin M. Despain

Quantum information processing requires a high degree of isolation from the detrimental effects of the environment as well as an extremely precise level of control on the way quantum dynamics unfolds in the information-processing system. In…

Quantum Physics · Physics 2014-04-07 J. Zhang , L. -C. Kwek , Erik Sjöqvist , D. M. Tong , P. Zanardi

The quantum Fourier transform (QFT), a quantum analog of the classical Fourier transform, has been shown to be a powerful tool in developing quantum algorithms. However, in classical computing there is another class of unitary transforms,…

Quantum Physics · Physics 2007-05-23 Amir Fijany , Colin P. Williams

We study in detail the effect of quantum decoherence in neutrino oscillations. We adopt a phenomenological approach that allows us to parametrize the energy dependence of the decoherence effects resulting from the modification of the…

High Energy Physics - Phenomenology · Physics 2025-12-11 Bikash Kumar Acharya , Indra Kumar Banerjee , Ujjal Kumar Dey

Quantum decoherence-the loss of quantum coherence due to interactions with an environment-plays a central role in quantum transport, and controlling this ubiquitous yet inevitable phenomenon is essential for practical quantum technologies.…

Mesoscale and Nanoscale Physics · Physics 2026-05-01 Xian-Peng Zhang , Yan-Qing Feng , Wanxiang Feng , Yugui Yao

The most common error models for quantum computers assume the independence of errors on different qubits. However, most noise mechanisms have some correlations in space. We show how to improve quantum information processing for few-qubit…

Quantum Physics · Physics 2018-12-19 Vickram N. Premakumar , Robert Joynt

We introduce a novel scheme for one-way quantum computing (QC) based on the use of information encoded qubits in an effective cluster state resource. With the correct encoding structure, we show that it is possible to protect the entangled…

Quantum Physics · Physics 2009-11-13 M. S. Tame , M. Paternostro , M. S. Kim

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…

We discuss the various manifestations of quantum decoherence in the forms of dephasing, entanglement with the environment, and revelation of "which-path" information. As a specific example, we consider an electron interference experiment.…

Quantum Physics · Physics 2015-05-13 Jen-Tsung Hsiang , L. H. Ford

It is shown how environmental decoherence plays an essential and constructive role in a quantum mechanical theory of brain process that has significant explanatory power.

Quantum Physics · Physics 2007-05-23 Henry P. Stapp

Coupling to the environment typically suppresses quantum properties of physical systems via decoherence mechanisms. This is one of the main obstacles in practical implementations of quantum protocols. In this work we show how decoherence…

Quantum Physics · Physics 2023-02-22 Katarzyna Roszak , Jarosław K. Korbicz

We investigate decoherence channels that are modelled as a sequence of collisions of a quantum system (e.g., a qubit) with particles (e.g., qubits) of the environment. We show that collisions induce decoherence when a bi-partite interaction…

Quantum Physics · Physics 2009-11-11 Mario Ziman , Vladimir Buzek

By means of a simple example it is demonstrated that the task of finding and identifying certain patterns in an otherwise (macroscopically) unstructured picture (data set) can be accomplished efficiently by a quantum computer. Employing the…

Quantum Physics · Physics 2009-11-07 Ralf Schützhold

Noise and decoherence are two major obstacles to the implementation of large-scale quantum computing. Because of the no-cloning theorem, which says we cannot make an exact copy of an arbitrary quantum state, simple redundancy will not work…

Quantum Physics · Physics 2020-07-09 Nam H. Nguyen , Elizabeth C. Behrman , James E. Steck

Quantum decoherence refers to the phenomenon when the interaction of a quantum system with its environment results in the degradation of quantum coherence. Decoherence is considered to be the most popular mechanism responsible for the…

Quantum Physics · Physics 2026-02-25 Mohd Shoaib Qureshi , Tabish Qureshi