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Related papers: Wigner function negativity and contextuality in qu…

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The role of permutation gates for universal quantum computing is investigated. The \lq magic' of computation is clarified in the permutation gates, their eigenstates, the Wootters discrete Wigner function and state-dependent contextuality…

Quantum Physics · Physics 2017-08-22 Michel Planat , Rukhsan-Ul-Haq

Anomalous weak values and Wigner function's negativity are well known witnesses of quantum contextuality. We show that these effects occur when analyzing the energetics of a single qubit gate generated by a resonant coherent field traveling…

This article comprises a review of both the quasi-probability representations of infinite-dimensional quantum theory (including the Wigner function) and the more recently defined quasi-probability representations of finite-dimensional…

Quantum Physics · Physics 2011-10-18 Christopher Ferrie

We present a continuous variable tomography scheme that reconstructs the Husimi Q-function (Wigner function) by Lagrange interpolation, using measurements of the Q-function (Wigner function) at the Padua points, the optimal sampling points…

Quantum Physics · Physics 2018-03-07 Olivier Landon-Cardinal , Luke C. G. Govia , Aashish A. Clerk

Recent results on the non-universality of fault-tolerant gate sets underline the critical role of resource states, such as magic states, to power scalable, universal quantum computation. Here we develop a resource theory, analogous to the…

Quantum Physics · Physics 2015-06-16 Victor Veitch , Seyed Ali Hamed Mousavian , Daniel Gottesman , Joseph Emerson

We propose a method for classical simulation of finite-dimensional quantum systems, based on sampling from a quasiprobability distribution, i.e., a generalized Wigner function. Our construction applies to all finite dimensions, with the…

Quantum Physics · Physics 2020-03-10 Robert Raussendorf , Juani Bermejo-Vega , Emily Tyhurst , Cihan Okay , Michael Zurel

We construct a topological space to study contextuality in quantum mechanics. The resulting space is a classifying space in the sense of algebraic topology. Cohomological invariants of our space correspond to physical quantities relevant to…

Quantum Physics · Physics 2021-06-07 Cihan Okay , Daniel Sheinbaum

In the framework of noisy quantum homodyne tomography with efficiency parameter $0 < \eta \leq 1$, we propose two estimators of a quantum state whose density matrix elements $\rho_{m,n}$ decrease like $e^{-B(m+n)^{r/ 2}}$, for fixed known…

Statistics Theory · Mathematics 2009-11-13 Jean-Marie Aubry , Cristina Butucea , Katia Méziani

We study the class of discrete Wigner functions proposed by Gibbons et al. [Phys. Rev. A 70, 062101 (2004)] to describe quantum states using a discrete phase-space based on finite fields. We find the extrema of such functions for small…

Quantum Physics · Physics 2008-09-02 Andrea Casaccino , Ernesto F. Galvao , Simone Severini

This dissertation serves as a general introduction to Wigner functions, phase space, and quantum metrology but also strives to be useful as a how-to guide for those who wish to delve into the realm of using continuous variables, to describe…

Quantum Physics · Physics 2016-05-05 Bryan Gard

We develop theoretical methods for the implementation of creation and destruction operators in separate registers of a quantum computer, allowing for a transparent and dynamical creation and destruction of particle modes in second…

High Energy Physics - Theory · Physics 2024-06-12 Juan José Gálvez-Viruet , Felipe J. Llanes-Estrada

Experimental realization of various quantum states of interest has become possible in the recent past due to the rapid developments in the field of quantum state engineering. Nonclassical properties of such states have led to various…

Quantum Physics · Physics 2022-06-07 Kathakali Mandal , Nasir Alam , Amit Verma , Anirban Pathak , J. Banerji

The hybrid approach to quantum computation simultaneously utilizes both discrete and continuous variables which offers the advantage of higher density encoding and processing powers for the same physical resources. Trapped ions, with…

Quantum Physics · Physics 2020-05-06 H. C. J. Gan , Gleb Maslennikov , Ko-Wei Tseng , Chihuan Nguyen , Dzmitry Matsukevich

We show that partial transposition for pure and mixed two-particle states in a discrete $N$-dimensional Hilbert space is equivalent to a change in sign of a "momentum-like" variable of one of the particles in the Wigner function for the…

Quantum Physics · Physics 2017-05-29 Yehuda B. Band , Pier A. Mello

Mutually unbiased bases and discrete Wigner functions are closely, but not uniquely related. Such a connection becomes more interesting when the Hilbert space has a dimension that is a power of a prime $N=d^n$, which describes a composite…

Quantum Physics · Physics 2009-11-13 Gunnar Bjork , Jose L. Romero , Andrei B. Klimov , Luis L. Sanchez-Soto

In this paper, we correct a mistake we made in [Phys. Rev. Lett. $\textbf{122}$, 190402 (2019)] and [Phys. Rev. A $\textbf{103}$, 012213 (2021)] regarding the Wigner function of the so-called smoothed Weak-Valued state (SWV state). Here…

Quantum Physics · Physics 2025-08-07 Kiarn T. Laverick , Areeya Chantasri , Howard M. Wiseman

In continuous-variable quantum computation, identifying key elements that enable a quantum computational advantage is a long-standing issue. Starting from the standard results on the necessity of Wigner negativity, we develop a…

Quantum Physics · Physics 2025-03-12 Massimo Frigerio , Antoine Debray , Nicolas Treps , Mattia Walschaers

We give a definition for the Wigner function for quantum mechanics on the Bohr compactification of the real line and prove a number of simple consequences of this definition. We then discuss how this formalism can be applied to loop quantum…

Mathematical Physics · Physics 2008-11-26 Christopher J. Fewster , Hanno Sahlmann

Conditional evolution is crucial for generating non-Gaussian resources for quantum information tasks in the continuous variable scenario. However, tools are lacking for a convenient representation of heralded process in terms of quantum…

Quantum Physics · Physics 2013-02-22 Franck Ferreyrol , Nicolò Spagnolo , Rémi Blandino , Marco Barbieri , Rosa Tualle-Brouri

We discuss questions pertaining to the definition of `momentum', `momentum space', `phase space', and `Wigner distributions'; for finite dimensional quantum systems. For such systems, where traditional concepts of `momenta' established for…

Quantum Physics · Physics 2009-11-11 S. Chaturvedi , E. Ercolessi , G. Marmo , G. Morandi , N. Mukunda , R. Simon