A semi-agnostic ansatz with variable structure for variational quantum algorithms

Quantum machine learning-and specifically Variational Quantum Algorithms (VQAs)-offers a powerful, flexible paradigm for programming near-term quantum computers, with applications in chemistry, metrology, materials science, data science, and mathematics. Here, one trains an ansatz, in the form of a...

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Detalles Bibliográficos
Autores: Bilkis, Matias|||0000-0001-7491-5666, Cerezo, Marco|||0000-0002-2757-3170, Verdon, Guillaume|||0000-0001-6583-5760, Coles, Patrick|||0000-0001-9879-8425, Cincio, Lukasz
Tipo de recurso: artículo
Fecha de publicación:2023
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:285875
Acceso en línea:https://ddd.uab.cat/record/285875
https://dx.doi.org/urn:doi:10.1007/s42484-023-00132-1
Access Level:acceso abierto
Palabra clave:Quantum machine learning
Variational quantum algorithms
Quantum circuit discovery
Descripción
Sumario:Quantum machine learning-and specifically Variational Quantum Algorithms (VQAs)-offers a powerful, flexible paradigm for programming near-term quantum computers, with applications in chemistry, metrology, materials science, data science, and mathematics. Here, one trains an ansatz, in the form of a parameterized quantum circuit, to accomplish a task of interest. However, challenges have recently emerged suggesting that deep ansatzes are difficult to train, due to flat training landscapes caused by randomness or by hardware noise. This motivates our work, where we present a variable structure approach to build ansatzes for VQAs. Our approach, called VAns (Variable Ansatz), applies a set of rules to both grow and (crucially) remove quantum gates in an informed manner during the optimization. Consequently, VAns is ideally suited to mitigate trainability and noise-related issues by keeping the ansatz shallow. We employ VAns in the variational quantum eigensolver for condensed matter and quantum chemistry applications, in the quantum autoencoder for data compression and in unitary compilation problems showing successful results in all cases.