Results 61 to 70 of about 5,471 (136)
Simple Algorithm for Partial Quantum Search
, 2005 Quite often in database search, we only need to extract portion of the information about the satisfying item. Recently Radhakrishnan & Grover [RG] considered this problem in the following form: the database of $N$ items was divided into $K$ equally sized
C. Zalka +3 more
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Gibbs-preserving maps outperform thermal operations in the quantum regime
New Journal of Physics, 2015 In this brief paper, we compare two frameworks for characterizing possible operations in quantum thermodynamics. One framework considers thermal operations—unitaries which conserve energy.
Philippe Faist +2 more
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Is Einsteinian no-signalling violated in Bell tests?
Open Physics, 2017 Relativistic invariance is a physical law verified in several domains of physics. The impossibility of faster than light influences is not questioned by quantum theory.
Kupczynski Marian
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Efficient Concentration Protocols for the Single-Photon Entanglement State with Polarization Feature
Frontiers in Physics, 2017 We propose two efficient entanglement concentration protocols (ECPs) for arbitrary less-entangled single-photon entanglement state, in which the photon qubit has the polarization feature.
Lan Zhou +6 more
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Extracting the physical sector of quantum states
New Journal of Physics, 2017 The physical nature of any quantum source guarantees the existence of an effective Hilbert space of finite dimension, the physical sector, in which its state is completely characterized with arbitrarily high accuracy.
D Mogilevtsev +8 more
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Smallest state spaces for which bipartite entangled quantum states are separable
New Journal of Physics, 2015 According to usual definitions, entangled states cannot be given a separable decomposition in terms of products of local density operators. If we relax the requirement that the local operators be positive, then an entangled quantum state may admit a ...
Hussain Anwar +3 more
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Quantum entanglement and spin control in silicon nanocrystal. [PDF]
PLoS ONE, 2012 Selective coherence control and electrically mediated exchange coupling of single electron spin between triplet and singlet states using numerically derived optimal control of proton pulses is demonstrated.
Vesna Berec
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Dynamical decoupling leads to improved scaling in noisy quantum metrology
New Journal of Physics, 2016 We consider the usage of dynamical decoupling in quantum metrology, where the joint evolution of system plus environment is described by a Hamiltonian. We show that by ultra-fast unitary control operations acting locally only on system qubits, noise can ...
Pavel Sekatski +2 more
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Calculating the relative entropy of entanglement
, 2000 We extend Vedral and Plenio's theorem (theorem 3 in Phys. Rev. A 57, 1619) to a more general case, and obtain the relative entropy of entanglement for a class of mixed states, this result can also follow from Rains' theorem 9 in Phys. Rev.
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The thermodynamic cost of quantum operations
New Journal of Physics, 2016 The amount of heat generated by computers is rapidly becoming one of the main problems for developing new generations of information technology. The thermodynamics of computation sets the ultimate physical bounds on heat generation.
D J Bedingham, O J E Maroney
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