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arXiv · 2605.09616

A Hybrid Classical-Quantum Annealing Algorithm for the TSP

Siwei Hu·Victor Lopata·Salvatore Sinno·Shruthi Thuravakkath·Paolo Zuliani
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Abstract

Hybrid quantum-classical algorithms can help mitigating the physical limitations of current quantum devices, particularly the low qubit count and the reduced topological connectivity. In this paper, we propose a hybrid technique to solve a well-known NP-hard optimization problem: the Traveling Salesperson Problem (TSP). Our approach is based on a graph contraction technique that removes most of the dimensionality of the original problem instance, producing a sub-TSP of a size suitable to be efficiently solved by a quantum device. The performance of our approach is first demonstrated on classical quantum simulation using Path Integral Monte Carlo, and then run on a D-Wave quantum annealer.

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Siwei Hu, Victor Lopata, Salvatore Sinno, Shruthi Thuravakkath, Paolo Zuliani. 2026-05-10. A Hybrid Classical-Quantum Annealing Algorithm for the TSP. https://arxiv.org/abs/2605.09616

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