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Related papers: Maintaining coherence in Quantum Computers

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Quantum coherence is an important quantum resource and it is intimately related to various research fields. The geometric coherence is a coherence measure both operationally and geometrically. We study the trade-off relation of geometric…

Quantum Physics · Physics 2023-10-25 Bingyu Hu , Ming-Jing Zhao

Quantum coherence, the ability to control the phases in superposition states is a resource, and it is of crucial importance, therefore, to understand how it is consumed in use. It has been suggested that catalytic coherence is possible,…

Quantum Physics · Physics 2018-09-26 Joan A. Vaccaro , Sarah Croke , Stephen M. Barnett

We present an experiment where the quantum coherence in the edge states of the integer quantum Hall regime is tuned with a decoupling gate. The coherence length is determined by measuring the visibility of quantum interferences in a…

Mesoscale and Nanoscale Physics · Physics 2012-07-11 P-A. Huynh , F. Portier , H. le Sueur , G. Faini , U. Gennser , D. Mailly , F. Pierre , W. Wegscheider , P. Roche

Recently, it was realized that use of the properties of quantum mechanics might speed up certain computations dramatically. Interest in quantum computation has since been growing. One of the main difficulties of realizing quantum…

Quantum Physics · Physics 2008-02-03 Peter W. Shor

Cooperative effects in the loss (the amplitude damping) and decoherence (the phase damping) of the qubits (two-state quantum systems) due to the inevitable coupling to the same environment are investigated. It is found that the qubits…

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

Decoherence-free subspaces allow for the preparation of coherent and entangled qubits for quantum computing. Decoherence can be dramatically reduced, yet dissipation is an integral part of the scheme in generating stable qubits and…

Quantum Physics · Physics 2009-11-07 Ben Tregenna , Almut Beige , Peter L. Knight

We analyze the problem of a quantum computer in a correlated environment protected from decoherence by QEC using a perturbative renormalization group approach. The scaling equation obtained reflects the competition between the dimension of…

Quantum Physics · Physics 2007-05-23 E. Novais , Eduardo R. Mucciolo , Harold U. Baranger

We analyse dissipation in quantum computation and its destructive impact on efficiency of quantum algorithms. Using a general model of decoherence, we study the time evolution of a quantum register of arbitrary length coupled with an…

Quantum Physics · Physics 2015-06-26 G. Massimo Palma , Kalle-Antti Suominen , Artur K. Ekert

Quantum correlation includes quantum entanglement and quantum discord. Both entanglement and discord have a common necessary condition--------quantum coherence or quantum superposition. In this paper, we attempt to give an alternative…

Quantum Physics · Physics 2014-09-23 Chang-shui Yu , Yang Zhang , Haiqing Zhao

Quantum computing relies on processing information within a quantum system with many continuous degrees of freedom. The practical implementation of this idea requires complete control over all of the 2^n independent amplitudes of a…

Condensed Matter · Physics 2007-05-23 M. I. Dyakonov

Quantum information technologies require careful control for generating and preserving a desired target quantum state. The biggest practical obstacle is, of course, decoherence. Therefore, the reachability analysis, which in our scenario…

Quantum Physics · Physics 2019-05-30 Kohei Kobayashi , Naoki Yamamoto

We describe quantum controllability under the influences of the quantum decoherence induced by the quantum control itself. It is shown that, when the controller is considered as a quantum system, it will entangle with its controlled system…

Quantum Physics · Physics 2009-11-11 Fei Xue , S. X. Yu , C. P. Sun

Recently developed quantum algorithms suggest that quantum computers can solve certain problems and perform certain tasks more efficiently than conventional computers. Among other reasons, this is due to the possibility of creating…

Quantum Physics · Physics 2007-05-23 Rolando D. Somma

The ability to live in coherent superpositions is a signature trait of quantum systems and constitutes an irreplaceable resource for quantum-enhanced technologies. However, decoherence effects usually destroy quantum superpositions. It has…

The coherence of an individual quantum state can be meaningfully discussed only when referring to a preferred basis. This arbitrariness can however be lifted when considering sets of quantum states. Here we introduce the concept of set…

Quantum Physics · Physics 2021-06-08 Sébastien Designolle , Roope Uola , Kimmo Luoma , Nicolas Brunner

Quantifying the resources available to a quantum computer appears to be necessary to separate quantum from classical computation. Among them, entanglement, nonstabilizerness and coherence are arguably of great significance. We introduce…

An intense effort is being made today to build a quantum computer. Instead of presenting what has been achieved, I invoke here analogies from the history of science in an attempt to glimpse what the future might hold. Quantum computing is…

Quantum Physics · Physics 2011-10-17 G. S. Paraoanu

When a confined system interacts with its walls (treated quantum mechanically), there is an intertwining of degrees of freedom. We show that this need not lead to entanglement, hence decoherence. It will generally lead to error. The wave…

Quantum Physics · Physics 2008-11-26 L. Schulman

Quantum coherence, the ability of a quantum system to be in a superposition of orthogonal quantum states, is a distinct feature of the quantum mechanics, thus marking a deviation from classical physics. Coherence finds its applications in…

Quantum Physics · Physics 2023-01-18 Najmeh Etehadi Abari , Andrey Rakhubovsky , Radim Filip

Quantum measurements necessarily disturb the state of physical system. Once we perform a complete measurement, the system undergoes decoherence and loses its coherence. If there is no disturbance, the state retains all of its coherence. It…

Quantum Physics · Physics 2018-10-10 Gautam Sharma , Arun Kumar Pati