QUROPE Quantum Information Processing and Communication in Europe

Author(s): Eyal Buks

Multistability is experimentally observed in a variety of quantum systems but cannot be derived from any theoretical model that is based on a monostable master equation. The author investigates the relation between disentanglement and multistability in the few-spin transverse Ising model and finds that multistability can be obtained in the presence of spontaneous disentanglement.

[Phys. Rev. A 110, 012439] Published Mon Jul 15, 2024

Author(s): Katarzyna Siudzińska

We use symmetric measurement operators to construct quantum channels that provide a further generalization of generalized Pauli channels. The resulting maps are bistochastic but, in general, no longer mixed unitary. We analyze their important properties, such as complete positivity and the ability t…

[Phys. Rev. A 110, 012440] Published Mon Jul 15, 2024

Author(s): Ming Yang, Dongkai Zhang, and Lixiang Chen

Recent advancements have expanded Hardy's nonlocality arguments into multisetting and multidimensional systems to enhance quantum correlations. In comparison with Hardy's nonlocality argument, Cabello's nonlocality argument (CNA) emerges as a superior choice for illustrating nonlocal features. An op…

[Phys. Rev. A 110, 012441] Published Mon Jul 15, 2024

Author(s): Zi-Jian Xu and Jun-Hong An

Permitting the transmission of unknown quantum states over long distances by using entanglement, quantum teleportation serves as an important building block for many quantum technologies. However, in the noisy intermediate-scale quantum era, the practical realization of quantum teleportation is inev…

[Phys. Rev. A 110, 012442] Published Mon Jul 15, 2024

Author(s): Naoki Masuda

A machine-learning framework predicts when a complex system, such as an ecosystem or a power grid, will undergo a critical transition.

[Physics 17, 110] Published Mon Jul 15, 2024

Author(s): Hui-Nan Wu, Yu-Huai Li, Bo Li, Xiang You, Run-Ze Liu, Ji-Gang Ren, Juan Yin, Chao-Yang Lu, Yuan Cao, Cheng-Zhi Peng, and Jian-Wei Pan

The emergence of quantum mechanics and general relativity has transformed our understanding of the natural world significantly. However, integrating these two theories presents immense challenges, and their interplay remains untested. Recent theoretical studies suggest that the single-photon interfe…

[Phys. Rev. Lett. 133, 020201] Published Fri Jul 12, 2024

Author(s): Michael Schirber

Experiments on a bed of plastic beads reveal a temperature-dependent stiffening over time, which appears to be related to molecular-scale deformations.

[Physics 17, 112] Published Fri Jul 12, 2024

Author(s): Julie Gould

Sonification and other multisensorial approaches offer powerful tools to analyze data, help visually impaired researchers, communicate science, and create science-inspired art.

[Physics 17, 113] Published Fri Jul 12, 2024

Author(s): M. Yassine Naghmouchi and Wesley da Silva Coelho

This paper presents a hybrid classical-quantum approach to solve mixed-integer linear programming (MILP) using neutral-atom quantum computations. We apply Benders decomposition (BD) to segment MILPs into a master problem (MP) and a subproblem, where the MP is addressed using a neutral-atom device, a…

[Phys. Rev. A 110, 012434] Published Fri Jul 12, 2024

Author(s): Ashutosh Goswami, Mehdi Mhalla, and Valentin Savin

A fault-tolerant way to prepare logical code states of Q1 codes, i.e., quantum polar codes encoding one qubit, was recently proposed. The fault tolerance therein is guaranteed by an error detection gadget, where, if an error is detected during the preparation, one entirely discards the preparation. …

[Phys. Rev. A 110, 012438] Published Fri Jul 12, 2024

Author(s): Steven Herbert, Julien Sorci, and Yao Tang

We give an explicit construction to perform any n-qubit computational-basis-state transposition using Θ(n) gates. This nearly coincides with the lower bound Ω[n/log(nd)] on worst-case and average-case gate complexities to perform transpositions using a d-element gate set, which we also prove.

[Phys. Rev. A 110, 012437] Published Fri Jul 12, 2024

Author(s): Ming-Ming Wang and Xiao-Ying Zhang

Bayesian networks are powerful tools for probabilistic analysis and have been widely used in machine learning and data science. Unlike the time-consuming parameter training process of neural networks, Bayes classifiers constructed on Bayesian networks can make decisions based solely on statistical d…

[Phys. Rev. A 110, 012433] Published Fri Jul 12, 2024

Author(s): Jack Ceroni, Ian MacCormack, and Guillaume Verdon

We provide a rigorous proof of the approximate convergence of sliding-window quantum belief-propagation as outlined heuristically in the work of Bilgin and Poulin [Phys. Rev. B 81, 054106 (2010)], in the absence of the quantum Markov property. In particular, we confirm the hypothesis outlined in thi…

[Phys. Rev. A 110, 012435] Published Fri Jul 12, 2024

Author(s): Kan Takase, Fumiya Hanamura, Hironari Nagayoshi, J. Eli Bourassa, Rafael N. Alexander, Akito Kawasaki, Warit Asavanant, Mamoru Endo, and Akira Furusawa

The generation of a logical qubit called the Gottesman-Kitaev-Preskill (GKP) qubit in an optical traveling wave is a major challenge for realizing large-scale universal fault-tolerant optical quantum computers. Recently, probabilistic generation of elementary GKP qubits has been demonstrated using p…

[Phys. Rev. A 110, 012436] Published Fri Jul 12, 2024

Author(s): Katherine Wright

Observations of seven fast-moving stars at the center of a dense star cluster in the Milky Way reveal the presence of an intermediate-mass black hole, perhaps the most puzzling class of these dark objects.

[Physics 17, 114] Published Thu Jul 11, 2024

Author(s): Nikhil Karthik

Electron neutrinos produced by proton–proton collisions at the LHC have been experimentally observed.

[Physics 17, s80] Published Thu Jul 11, 2024

Author(s): Akshay Seshadri, Martin Ringbauer, Jacob Spainhour, Rainer Blatt, Thomas Monz, and Stephen Becker

As quantum devices become more complex and the requirements on these devices become more demanding, it is crucial to be able to verify the performance of such devices in a scalable and reliable fashion. A cornerstone task in this challenge is quantifying how close an experimentally prepared quantum …

[Phys. Rev. Lett. 133, 020402] Published Wed Jul 10, 2024

Author(s): Christian Bertoni, Jonas Haferkamp, Marcel Hinsche, Marios Ioannou, Jens Eisert, and Hakop Pashayan

We provide practical and powerful schemes for learning properties of a quantum state using a small number of measurements. Specifically, we present a randomized measurement scheme modulated by the depth of a random quantum circuit in one spatial dimension. This scheme interpolates between two known …

[Phys. Rev. Lett. 133, 020602] Published Wed Jul 10, 2024

Author(s): Pingal Pratyush Nath, Debashis Saha, Dipankar Home, and Urbasi Sinha

We theoretically formulate and experimentally demonstrate a secure scheme for semi-device-independent quantum random number generation by utilizing Leggett-Garg inequality violations, within a loophole-free photonic architecture. The quantification of the generated randomness is rigorously estimated…

[Phys. Rev. Lett. 133, 020802] Published Wed Jul 10, 2024

Author(s): Rachel Berkowitz

A statistical tool tests the long-held assumption that small-scale turbulence is isotropic.

[Physics 17, s77] Published Wed Jul 10, 2024