Separating Ansatz Discovery from Deployment on Larger Problems: Reinforcement Learning for Modular Circuit Design

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Turati, Gloria, Foderà, Simone, Nembrini, Riccardo, Dacrema, Maurizio Ferrari, Cremonesi, Paolo
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912933300142080
author Turati, Gloria
Foderà, Simone
Nembrini, Riccardo
Dacrema, Maurizio Ferrari
Cremonesi, Paolo
author_facet Turati, Gloria
Foderà, Simone
Nembrini, Riccardo
Dacrema, Maurizio Ferrari
Cremonesi, Paolo
contents As quantum computing continues to gain attention, there is growing interest in how classical machine learning can assist quantum workflows in practice. Automated circuit design, sometimes referred to as Quantum Architecture Search (QAS), is a natural application but relies on the ability to model the quantum system to support learning as the number of qubits grows. This challenge is central to QAS, and much of the current literature that proposes new ways to model the ansatz focuses on small systems, often around ten qubits. In this work, we propose a complementary approach that separates a small-scale structure discovery phase, where a reusable modular circuit block is learned on small instances where classical learning is feasible, from a deployment phase, where the blocks are used to create the ansatz required for larger problems. To this end, we introduce Reinforcement Learning for Variational Quantum Circuits (RLVQC), formulating QAS as a sequential decision-making problem. We evaluate our methodology on Quadratic Unconstrained Binary Optimization (QUBO) instances derived from Maximum Cut, Maximum Clique, and Minimum Vertex Cover. Our RLVQC Block model is trained to discover a modular two-qubit block that can generalize QAOA-style methods and that is often beneficial compared to learning non-modular ansatzes. The blocks discovered on n=8 instances remain effective when deployed on larger instances (n=12 and n=16), supporting the feasibility of reusing learned modular structure across problem sizes. While we do not aim to establish a new state-of-the-art solver or an advantage over classical methods, our results provide evidence that modular ansatz structure can be learned on smaller instances and then extended to larger ones without requiring learning on systems with a large number of qubits, where quantum computing becomes interesting but classical computation becomes impractical.
format Preprint
id arxiv_https___arxiv_org_abs_2507_16001
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Separating Ansatz Discovery from Deployment on Larger Problems: Reinforcement Learning for Modular Circuit Design
Turati, Gloria
Foderà, Simone
Nembrini, Riccardo
Dacrema, Maurizio Ferrari
Cremonesi, Paolo
Quantum Physics
Machine Learning
As quantum computing continues to gain attention, there is growing interest in how classical machine learning can assist quantum workflows in practice. Automated circuit design, sometimes referred to as Quantum Architecture Search (QAS), is a natural application but relies on the ability to model the quantum system to support learning as the number of qubits grows. This challenge is central to QAS, and much of the current literature that proposes new ways to model the ansatz focuses on small systems, often around ten qubits. In this work, we propose a complementary approach that separates a small-scale structure discovery phase, where a reusable modular circuit block is learned on small instances where classical learning is feasible, from a deployment phase, where the blocks are used to create the ansatz required for larger problems. To this end, we introduce Reinforcement Learning for Variational Quantum Circuits (RLVQC), formulating QAS as a sequential decision-making problem. We evaluate our methodology on Quadratic Unconstrained Binary Optimization (QUBO) instances derived from Maximum Cut, Maximum Clique, and Minimum Vertex Cover. Our RLVQC Block model is trained to discover a modular two-qubit block that can generalize QAOA-style methods and that is often beneficial compared to learning non-modular ansatzes. The blocks discovered on n=8 instances remain effective when deployed on larger instances (n=12 and n=16), supporting the feasibility of reusing learned modular structure across problem sizes. While we do not aim to establish a new state-of-the-art solver or an advantage over classical methods, our results provide evidence that modular ansatz structure can be learned on smaller instances and then extended to larger ones without requiring learning on systems with a large number of qubits, where quantum computing becomes interesting but classical computation becomes impractical.
title Separating Ansatz Discovery from Deployment on Larger Problems: Reinforcement Learning for Modular Circuit Design
topic Quantum Physics
Machine Learning
url https://arxiv.org/abs/2507.16001