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Related papers: Phase Squeezing of Quantum Hypergraph States

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Relative phase is treated as a physical quantity for two mode systems in quantum atom optics, adapting the Pegg-Barnett treatment of quantum optical phase to define a linear Hermitian relative phase operator via first introducing a complete…

Quantum Gases · Physics 2011-08-24 B J Dalton

We show that there is a sector of quantum general relativity which may be expressed in a completely holographic formulation in terms of states and operators defined on a finite boundary. The space of boundary states is built out of the…

High Energy Physics - Theory · Physics 2009-10-31 Lee Smolin

Fully entangled fraction (FEF) is a significant figure of merit for density matrices. In bipartite $ d \otimes d $ quantum systems, the threshold value FEF $ > 1/d $, carries significant implications for quantum information processing…

We investigate a family of quantum states defined by directed graphs, where the oriented edges represent interactions between ordered qubits. As a measure of entanglement, we adopt the Entanglement Distance - a quantity derived from the…

Quantum Physics · Physics 2025-05-19 Lucio De Simone , Roberto Franzosi

The graph state formalism is a useful abstraction of entanglement. It is used in some multipartite purification schemes and it adequately represents universal resources for measurement-only quantum computation. We focus in this paper on the…

Quantum Physics · Physics 2007-05-23 Mehdi Mhalla , Simon Perdrix

Quantum hypergraph states are the natural generalization of graph states. Here we investigate and analytically quantify entanglement and nonlocality for large classes of quantum hypergraph states. More specifically, we connect the geometric…

Quantum Physics · Physics 2026-03-17 Jan Nöller , Otfried Gühne , Mariami Gachechiladze

We present a method to reconstruct pure spatial qudits of arbitrary dimension $d$, which is based on a point diffraction interferometer. In the proposed scheme, the quantum states are codified in the discretized transverse position of a…

Quantum Physics · Physics 2023-01-27 Quimey Pears Stefano , Lorena Rebón , Claudio Iemmi

We study the entanglement content of the states employed in the Grover algorithm after the first oracle call when a few searched items are concerned. We then construct a link between these initial states and hypergraphs, which provides an…

Quantum Physics · Physics 2014-04-07 M. Rossi , D. Bruß , C. Macchiavello

This is a review of the geometry of quantum states using elementary methods and pictures. Quantum states are represented by a convex body, often in high dimensions. In the case of n-qubits, the dimension is exponentially large in n. The…

Quantum Physics · Physics 2019-08-12 Joseph Avron , Oded Kenneth

The interest in quantum-optical states confined in finite-dimensional Hilbert spaces has recently been stimulated by the progress in quantum computing, quantum-optical state preparation, and measurement techniques, in particular, by the…

Quantum Physics · Physics 2007-05-23 Adam Miranowicz , Wieslaw Leonski , Nobuyuki Imoto

Large-scale quantum computation is likely to require massive quantum error correction (QEC). QEC codes and circuits are described via the stabilizer formalism, which represents stabilizer states by keeping track of the operators that…

Quantum Physics · Physics 2017-11-22 Héctor J. García , Igor L. Markov , Andrew W. Cross

Quantum phase estimation protocols can provide a measuring method of phase shift with precision superior to standard quantum limit (SQL) due to the application of a nonclassical state of light. A squeezed vacuum state, whose variance in one…

Quantum Physics · Physics 2020-04-14 Juan Yu , Yue Qin , Jinliang Qin , Hong Wang , Zhihui Yan , Xiaojun Jia , Kunchi Peng

Graph states and hypergraph states are of wide interest in quantum information processing and foundational studies. Efficient verification of these states is a key to various applications. Here we propose a simple method for verifying…

Quantum Physics · Physics 2020-01-30 Huangjun Zhu , Masahito Hayashi

Quantum graph state is a special class of nonlocal state among multiple quantum particles, underpinning several nonclassical and promising applications such as quantum computing and quantum secret sharing. Recently, establishing quantum…

Quantum Physics · Physics 2025-08-14 Tingxiang Ji , Jianqing Liu , Zheshen Zhang

We analyze and further develop a new method to represent the quantum state of a system of $n$ qubits in a phase space grid of $N\times N$ points (where $N=2^n$). The method, which was recently proposed by Wootters and co--workers (Gibbons…

Quantum Physics · Physics 2009-11-10 Juan Pablo Paz , Augusto Jose Roncaglia , Marcos Saraceno

We introduce a class of states of a composite quantum system, the so-called cross states, that turn out to play a major role in the theory of entanglement for a genuinely infinite-dimensional bipartite system. In the case where at least one…

Mathematical Physics · Physics 2026-02-23 Paolo Aniello

The Standard Quantum Limit (SQL) in interferometric displacement measurement imposes a restriction on the precision of the measurement due to its quantum back-action noise. This limit can be surpassed over a broad frequency band by…

By using highly entangled states, quantum metrology guarantees precision impossible with classical measurements. Unfortunately such states can be very susceptible to noise, and it is a great challenge of the field to maintain quantum…

Quantum Physics · Physics 2020-03-25 Nathan Shettell , Damian Markham

We investigate the phase sensitivity of a Mach-Zehnder interferometer using a special class of generalized coherent states constructed from generalized Heisenberg and deformed $su(1,1)$ algebras. These states, derived from a perturbed…

Quantum Physics · Physics 2025-11-03 N. E. Abouelkhir , A. Slaoui , R. Ahl Laamara

W consider the problem of testing if a given matrix in the Hilbert space formulation of quantum mechanics or a function in the phase space formulation of quantum theory represent a quantum state. We propose several practical criteria to…

Mathematical Physics · Physics 2015-06-11 J. Tosiek , P. Brzykcy