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We investigate the possibility to apply quantum machine learning techniques for data analysis, with particular regard to an interesting use-case in high-energy physics. We propose an anomaly detection algorithm based on a parametrized…

Quantum Physics · Physics 2026-04-21 Simone Bordoni , Denis Stanev , Tommaso Santantonio , Stefano Giagu

In response to the demand for higher computational power, the number of computing nodes in high performance computers (HPC) increases rapidly. Exascale HPC systems are expected to arrive by 2020. With drastic increase in the number of HPC…

Distributed, Parallel, and Cluster Computing · Computer Science 2019-10-21 Siavash Ghiasvand , Florina M. Ciorba

Quantum theory is compatible with scenarios in which the order of operations is indefinite. Experimental investigations of such scenarios, all of which have been based on a process known as the quantum switch, have provided demonstrations…

Quantum Physics · Physics 2023-06-12 Tein van der Lugt , Jonathan Barrett , Giulio Chiribella

Unitary control and decoherence appear to be irreconcilable in quantum mechanics. When a quantum system interacts with an environment, control strategies usually fail due to decoherence. In this letter, we propose a time-optimal unitary…

Quantum Physics · Physics 2013-02-20 P. M. Poggi , F. C. Lombardo , D. A. Wisniacki

State of the art quantum computing architectures are founded on the decision to use scalable but faulty quantum hardware in conjunction with an efficient error correcting code capable of tolerating high error rates. The promised effect of…

Quantum Physics · Physics 2021-08-23 Alexandru Paler , Austin G. Fowler , Robert Wille

Identifying and calibrating quantitative dynamical models for physical quantum systems is important for a variety of applications. Here we present a closed-loop Bayesian learning algorithm for estimating multiple unknown parameters in a…

I. This paper is devoted to the problem of error detection with quantum codes. In the first part we examine possible problem settings for quantum error detection. Our goal is to derive a functional that describes the probability of…

Quantum Physics · Physics 2007-05-23 Alexei Ashikhmin , Alexander Barg , Emanuel Knill , Simon Litsyn

The problem of estimating an unknown phase $ \varphi $ using two-level probes in the presence of unital phase-covariant noise and using finite resources is investigated. We introduce a simple model in which the phase-imprinting operation on…

Quantum Physics · Physics 2016-10-05 Rosanna Nichols , Thomas R. Bromley , Luis A. Correa , Gerardo Adesso

The quest for precision in parameter estimation is a fundamental task in different scientific areas. The relevance of this problem thus provided the motivation to develop methods for the application of quantum resources to estimation…

Quantum Physics · Physics 2024-06-18 Valeria Cimini , Emanuele Polino , Mauro Valeri , Nicolò Spagnolo , Fabio Sciarrino

We give a definition of asymmetric universal entangling machine which entangles a system in an unknown state to a specially prepared ancilla. The machine produces a fixed state-independent amount of entanglement in exchange to a fixed…

Quantum Physics · Physics 2014-09-24 Dmitri Horoshko , Mikhail Kolobov , Sergei Kilin

Authentication of quantum sources is a crucial task in building reliable and efficient protocols for quantum-information processing. Steady progress vis-\`{a}-vis verification of quantum devices in the scenario with fully characterized…

Quantum Physics · Physics 2022-02-08 Aleksandra Gočanin , Ivan Šupić , Borivoje Dakić

This paper introduces quantum edge detection, aimed at locating boundaries of quantum domains where all particles share the same pure state. Focusing on the 1D scenario of a string of particles, we develop an optimal protocol for quantum…

Quantum computers promise to solve certain problems more efficiently than their digital counterparts. A major challenge towards practically useful quantum computing is characterizing and reducing the various errors that accumulate during an…

Applying post selection in each step of an iterated protocol leads to sensitive quantum dynamics that may be utilized to test and benchmark current quantum computers. An example of this type of protocols was originally proposed for the task…

Quantum Physics · Physics 2024-10-10 Adrian Ortega , Orsolya Kálmán , Tamás Kiss

Data-driven inference was recently introduced as a protocol that, upon the input of a set of data, outputs a mathematical description for a physical device able to explain the data. The device so inferred is automatically self-consistent,…

Quantum Physics · Physics 2021-12-10 Michele Dall'Arno , Asaph Ho , Francesco Buscemi , Valerio Scarani

The capability to reliably transmit and store quantum information is an essential building block for future quantum networks and processors. Gauging the ability of a communication link or quantum memory to preserve quantum correlations is…

The advent of quantum computers has justified the development of quantum machine learning algorithms , based on the adaptation of the principles of machine learning to the formalism of qubits. Among such quantum algorithms, anomaly…

Quantum Physics · Physics 2025-03-04 Sebastiano Corli , Lorenzo Moro , Daniele Dragoni , Massimiliano Dispenza , Enrico Prati

As quantum computing matures and moves toward broader accessibility through cloud-based platforms, ensuring the authenticity and integrity of quantum computations becomes an urgent concern. In this work, we propose a strategy to leverage…

Understanding the physical world fundamentally relies on the assumption that events are temporally ordered, with past events serving as causes for future ones. However, quantum mechanics permits events to occur in a superposition of causal…

Quantum Physics · Physics 2025-08-07 Dengke Qu , Quan Lin , Lei Xiao , Xiang Zhan , Peng Xue

A secure quantum identification system combining a classical identification procedure and quantum key distribution is proposed. Each identification sequence is always used just once and new sequences are ``refuelled'' from a shared provably…

Quantum Physics · Physics 2009-10-31 Miloslav Dusek , Ondrej Haderka , Martin Hendrych , Robert Myska