English
Related papers

Related papers: Connecting geometry and performance of two-qubit p…

200 papers

Variational quantum circuits (VQCs) are an essential tool in applying noisy intermediate-scale quantum computers to practical problems. VQCs are used as a central component in many algorithms, for example, in quantum machine learning,…

Quantum Physics · Physics 2025-12-18 Joona V. Pankkonen , Lauri Ylinen , Matti Raasakka , Ilkka Tittonen

Analytical and practical evidence indicates the advantage of quantum computing solutions over classical alternatives. Quantum-based heuristics relying on the variational quantum eigensolver (VQE) and the quantum approximate optimization…

Quantum Physics · Physics 2023-01-05 Sarthak Gupta , Vassilis Kekatos

Quantum Bit String Comparators (QBSC) operate on two sequences of n-qubits, enabling the determination of their relationships, such as equality, greater than, or less than. This is analogous to the way conditional statements are used in…

Quantum Physics · Physics 2023-11-23 Khuram Shahzad , Omar Usman Khan

The rapid progress in quantum computing (QC) and machine learning (ML) has attracted growing attention, prompting extensive research into quantum machine learning (QML) algorithms to solve diverse and complex problems. Designing…

Quantum Physics · Physics 2025-01-13 Samuel Yen-Chi Chen , Huan-Hsin Tseng , Hsin-Yi Lin , Shinjae Yoo

Hybrid quantum-classical systems make it possible to utilize existing quantum computers to their fullest extent. Within this framework, parameterized quantum circuits can be regarded as machine learning models with remarkable expressive…

Quantum Physics · Physics 2019-11-15 Marcello Benedetti , Erika Lloyd , Stefan Sack , Mattia Fiorentini

The feasibility of variational quantum algorithms, the most popular correspondent of neural networks on noisy, near-term quantum hardware, is highly impacted by the circuit depth of the involved parametrized quantum circuits (PQCs). Higher…

Machine Learning · Computer Science 2024-11-01 Philipp Schleich , Marta Skreta , Lasse B. Kristensen , Rodrigo A. Vargas-Hernández , Alán Aspuru-Guzik

The fragile nature of quantum information limits our ability to construct large quantities of quantum bits suitable for quantum computing. An important goal, therefore, is to minimize the amount of resources required to implement quantum…

Quantum Physics · Physics 2013-04-11 Adam Paetznick , Austin G. Fowler

Quantum algorithms based on parameterized quantum circuits (PQCs) have enabled a wide range of applications on near-term quantum devices. However, existing PQC architectures face several challenges, among which the ``barren plateaus"…

Quantum Physics · Physics 2026-01-09 Zhenyu Chen , Yuguo Shao , Zhengwei Liu , Zhaohui Wei

Training quantum neural networks (QNNs) using gradient-based or gradient-free classical optimisation approaches is severely impacted by the presence of barren plateaus in the cost landscapes. In this paper, we devise a framework for…

Quantum Physics · Physics 2024-06-04 Yidong Liao , Min-Hsiu Hsieh , Chris Ferrie

The use of quantum processing units (QPUs) promises speed-ups for solving computational problems. Yet, current devices are limited by the number of qubits and suffer from significant imperfections, which prevents achieving quantum…

Quantum Physics · Physics 2023-06-08 Hila Safi , Karen Wintersperger , Wolfgang Mauerer

Practical success of quantum learning models hinges on having a suitable structure for the parameterized quantum circuit. Such structure is defined both by the types of gates employed and by the correlations of their parameters. While much…

Quantum Physics · Physics 2024-02-29 Frederic Sauvage , Martin Larocca , Patrick J. Coles , M. Cerezo

When does a variational quantum algorithm converge to a globally optimal solution? Despite the large literature around variational approaches to quantum computing, the answer is largely unknown. We address this open question by developing a…

The use of Quantum Neural Networks (QNN) that are analogous to classical neural networks, has greatly increased in the past decade owing to the growing interest in the field of Quantum Machine Learning (QML). A QNN consists of three major…

Quantum Physics · Physics 2024-01-30 Koustubh Phalak , Swaroop Ghosh

Variational quantum algorithms are proposed to solve relevant computational problems on near term quantum devices. Popular versions are variational quantum eigensolvers and quantum ap- proximate optimization algorithms that solve ground…

Quantum Physics · Physics 2022-04-15 Lennart Bittel , Martin Kliesch

Quantum Machine Learning algorithms based on Variational Quantum Circuits (VQCs) are important candidates for useful application of quantum computing. It is known that a VQC is a linear model in a feature space determined by its…

Quantum Physics · Physics 2025-07-09 Slimane Thabet , Léo Monbroussou , Eliott Z. Mamon , Jonas Landman

Scaling of variational quantum algorithms to large problem sizes requires efficient optimization of random parameterized quantum circuits. For such circuits with uncorrelated parameters, the presence of exponentially vanishing gradients in…

Quantum Physics · Physics 2021-01-28 Tyler Volkoff , Patrick J. Coles

Parametrized quantum circuits initialized with random initial parameter values are characterized by barren plateaus where the gradient becomes exponentially small in the number of qubits. In this technical note we theoretically motivate and…

Quantum Physics · Physics 2019-12-11 Edward Grant , Leonard Wossnig , Mateusz Ostaszewski , Marcello Benedetti

We propose an efficient method for simultaneously optimizing both the structure and parameter values of quantum circuits with only a small computational overhead. Shallow circuits that use structure optimization perform significantly better…

Quantum Physics · Physics 2021-02-03 Mateusz Ostaszewski , Edward Grant , Marcello Benedetti

Quantum generative modeling is a growing area of interest for industry-relevant applications. With the field still in its infancy, there are many competing techniques. This work is an attempt to systematically compare a broad range of these…

Variational quantum algorithms (VQAs) optimize the parameters $\vec{\theta}$ of a parametrized quantum circuit $V(\vec{\theta})$ to minimize a cost function $C$. While VQAs may enable practical applications of noisy quantum computers, they…

Quantum Physics · Physics 2021-03-23 M. Cerezo , Akira Sone , Tyler Volkoff , Lukasz Cincio , Patrick J. Coles