Topology-Enhanced Superconducting Qubit Networks for In-Sensor Quantum Information Processing

TL;DR

This paper shows how the topology of superconducting qubit networks affects their magnetic response and demonstrates their potential for dual use in quantum sensing and quantum reservoir computing.

Contribution

It introduces the impact of network topology on magnetic response and proposes superconducting qubit arrays as versatile platforms for sensing and quantum information processing.

Findings

Cross-shaped arrays enhance magnetic flux response compared to linear arrays.

Network topology influences cooperative coupling and high-dimensional dynamics.

Arrays can function as both quantum sensors and reservoir computers.

Abstract

We investigate the influence of topology on the magnetic response of inductively coupled superconducting flux-qubit networks. Using exact diagonalization methods and linear response theory, we compare the magnetic response of linear and cross-shaped array geometries, used as paradigmatic examples. We find that the peculiar coupling matrix in cross-shaped arrays yields a significant enhancement of the magnetic flux response compared to linear arrays, this network-topology effect arising from cooperative coupling among the central and the peripheral qubits. These results establish quantitative design criteria for function-oriented superconducting quantum circuits, with direct implications for advancing performance in both quantum sensing and quantum information processing applications. Concerning the latter, by exploiting the non-linear and high-dimensional dynamics of such arrays, we demonstrate their suitability for quantum reservoir computing technology. This dual functionality suggests a novel platform in which the same device serves both as a quantum-limited electromagnetic sensor and as a reservoir capable of signal processing, enabling integrated quantum sensing and processing architectures.