Anonymous quantum sensing

TL;DR

This paper introduces an anonymous quantum sensing protocol that hides the positions of non-zero magnetic fields in a quantum network, ensuring security even if measurement outcomes are intercepted, and evaluates its sensitivity.

Contribution

The paper proposes a novel quantum sensing protocol that preserves the anonymity of magnetic field positions and analyzes its sensitivity using Fisher information.

Findings

The protocol maintains position anonymity even if measurement outcomes are stolen.

Sensitivity is finite unless non-zero magnetic fields have identical amplitudes.

The approach enables secure quantum sensing with preserved positional privacy.

Abstract

A lot of attention has been paid to a quantum-sensing network for detecting magnetic fields in different positions. Recently, cryptographic quantum metrology was investigated where the information of the magnetic fields is transmitted in a secure way. However, sometimes, the positions where non-zero magnetic fields are generated could carry important information. Here, we propose an anonymous quantum sensor where an information of positions having non-zero magnetic fields is hidden after measuring magnetic fields with a quantum-sensing network. Suppose that agents are located in different positions and they have quantum sensors. After the quantum sensors are entangled, the agents implement quantum sensing that provides a phase information if non-zero magnetic fields exist, and POVM measurement is performed on quantum sensors. Importantly, even if the outcomes of the POVM measurement is stolen by an eavesdropper, information of the positions with non-zero magnetic fields is still unknown for the eavesdropper in our protocol. In addition, we evaluate the sensitivity of our proposed quantum sensors by using Fisher information when there are at most two positions having non-zero magnetic fields. We show that the sensitivity is finite unless these two (non-zero) magnetic fields have exactly the same amplitude. Our results pave the way for new applications of quantum-sensing network.