Work

Resource-efficient variational quantum solver for the traveling salesman problem and its silicon photonics implementation

Year: 2026

Type: article

Abstract: The traveling salesman problem is a well-known example of computationally-hard combinatorial problem for classical machines. Here, we propose a novel variational quantum algorithm to solve it. The method is based on the preparation of two maximally entangled quantum registers whose correlations are assigned to different paths between pairs of cities. For N cities, this encoding requires 2 ⌈ log 2 ⁡ N ⌉ qubits and the solution to the problem is directly found in the correlation matrix of the two registers composing the overall trial state. As a proof-of-concept experiment, we implement this algorithm for generic problems with four cities on a reconfigurable room-temperature silicon photonic circuit with integrated photon-pair sources, used to initialize maximally entangled path-encoded single-photon states.

Source: Quantum Science and Technology

DOI: 10.1088/2058-9565/ae8df2

Authors: Alessio Baldazzi, Stefano Azzini, Lorenzo Pavesi

Institution: University of Trento

Language: English

Topic: Quantum Computing Algorithms and Architecture

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,895

Funders: Provincia Autonoma di Trento, Horizon 2020 Framework Programme