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Related papers: Phase-Covariant Quantum Benchmarks

200 papers

We present a Bell-state analyzer for time-bin qubits allowing the detection of three out of four Bell-states with linear optics, two detectors and no auxiliary photons. The theoretical success rate of this scheme is 50%. A teleportation…

Quantum Physics · Physics 2009-11-13 J. A. W. van Houwelingen , A. Beveratos , N. Brunner , N. Gisin , H. Zbinden

We describe a general framework to study covariant symmetric broadcasting maps for mixed qubit states. We explicitly derive the optimal N to M superbroadcasting maps, achieving optimal purification of the single-site output copy, in both…

Quantum Physics · Physics 2007-05-23 Francesco Buscemi , Giacomo Mauro D'Ariano , Chiara Macchiavello , Paolo Perinotti

The nonnegative Wigner function of all quantum states involved in teleportation of Gaussian states using the standard continuous-variable teleportation protocol means that there is a local realistic phase-space description of the process.…

Quantum Physics · Physics 2009-11-10 Carlton M. Caves , Krzysztof Wodkiewicz

In this paper we propose two schemes for teleportation of a sub-class of tripartite states, the first one with the four-qubit cluster state and the second one with two Bell pairs as entanglement channels. A four-qubit joint measurement in…

Quantum Physics · Physics 2018-05-23 Dintomon Joy , M Sabir

In this paper, we introduce a new approach to quantum benchmarking inspired by quantum verification motivating new paradigms of quantum benchmarking. Our proposed benchmark not only serves as a robust indicator of computational capability…

Quantum Physics · Physics 2024-04-17 Johannes Frank , Elham Kashefi , Dominik Leichtle , Michael de Oliveira

Quantum teleportation is an essential capability for quantum networks, allowing the transmission of quantum bits (qubits) without a direct exchange of quantum information. Its implementation between distant parties requires teleportation of…

Quantum Physics · Physics 2023-04-10 Dario Lago-Rivera , Jelena V. Rakonjac , Samuele Grandi , Hugues de Riedmatten

We present a method to create a variety of interesting gates by teleporting quantum bits through special entangled states. This allows, for instance, the construction of a quantum computer based on just single qubit operations, Bell…

Quantum Physics · Physics 2009-10-31 Daniel Gottesman , Isaac L. Chuang

We present measurements of single-qubit gate errors for a superconducting qubit. Results from quantum process tomography and randomized benchmarking are compared with gate errors obtained from a double pi pulse experiment. Randomized…

Mesoscale and Nanoscale Physics · Physics 2009-03-08 J. M. Chow , J. M. Gambetta , L. Tornberg , Jens Koch , Lev S. Bishop , A. A. Houck , B. R. Johnson , L. Frunzio , S. M. Girvin , R. J. Schoelkopf

Randomized benchmarking is a powerful technique to efficiently estimate the performance and reliability of quantum gates, circuits and devices. Here we propose to perform randomized benchmarking in a coherent way, where superpositions of…

Quantum Physics · Physics 2021-07-14 Jorge Miguel-Ramiro , Alexander Pirker , Wolfgang Dür

We consider the probability by which quantum phase measurements of a given precision can be done successfully. The least upper bound of this probability is derived and the associated optimal state vectors are determined. The probability…

Quantum Physics · Physics 2009-02-14 Thomas Schürmann

We present a method to test quantum behavior of quantum information processing devices, such as quantum memories, teleportation devices, channels and quantum key distribution protocols. The test of quantum behavior can be phrased as the…

Quantum Physics · Physics 2008-03-07 Hauke Häseler , Tobias Moroder , Norbert Lütkenhaus

Quantum measurements with feed-forward are crucial components of fault-tolerant quantum computers. We show how the error rate of such a measurement can be directly estimated by fitting the probability that successive randomly compiled…

Quantum Physics · Physics 2025-02-04 Darian McLaren , Matthew A. Graydon , Ali Assem Mahmoud , Joel J. Wallman

In the formalism of measurement based quantum computation we start with a given fixed entangled state of many qubits and perform computation by applying a sequence of measurements to designated qubits in designated bases. The choice of…

Quantum Physics · Physics 2007-05-23 Richard Jozsa

The present article proposes a measure of correlation for multiqubit mixed states. The measure is defined recursively, accumulating the correlation of the subspaces, making it simple to calculate without using of regression. Unlike usual…

We introduce sequential analysis in quantum information processing, by focusing on the fundamental task of quantum hypothesis testing. In particular our goal is to discriminate between two arbitrary quantum states with a prescribed error…

Coherent superpositions are one of the hallmarks of quantum mechanics and are vital for any quantum mechanical device to outperform the classically achievable. Generically, superpositions are verified in interference experiments, but…

Quantum Physics · Physics 2020-03-04 Benjamin Dive , Nikolaos Koukoulekidis , Stefanos Mousafeiris , Florian Mintert

We study bidirectional teleportation while explicitly taking into account an environment. This environment initially causes pure dephasing decoherence of the Bell state which assists teleportation. We find that when teleportation is…

Quantum Physics · Physics 2025-04-01 Tytus Harlender , Katarzyna Roszak

We discuss a pairwise-comparison viewpoint on finite families of qubit states. Starting from transition amplitudes between pure states, we distinguish three associated levels of comparison data: complex amplitudes, transition probabilities,…

Mathematical Physics · Physics 2026-05-07 Jean-Pierre Magnot

In this paper we present an optimal protocol by which an unknown state on a Hilbert space of dimension $N$ can be approximately stored in an $M$-dimensional quantum system or be approximately teleported via an $M$-dimensional quantum…

Quantum Physics · Physics 2009-11-07 Thomas Laustsen , Klaus Molmer

Bidirectional quantum teleportation is a fundamental protocol for exchanging quantum information between two quantum nodes. All bidirectional quantum teleportation protocols till now have achieved a maximum efficiency of $40\%$. Here, we…

Quantum Physics · Physics 2023-03-22 Javid A Malik , Muzaffar Qadir Lone , Rayees A Malla
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