Our paper demonstrating a new protocol for quantum-enhanced sensing of spatially distributed fields has been published in Physical Review Letters. This work was carried out in close collaboration between our group and the group of Prof. Wolfgang Dür here in Innsbruck. A news article can be found here. The abstract and paper link are provided below. Congratulations to both teams!
The paper: Experimental Distributed Quantum Sensing in a Noisy Environment, J. Bate, A. Hamann, M. Canteri, A. Winkler, Z.X. Koong, V. Krutyanski, W. Dür, and B.P. Lanyon, Phys. Rev. Lett. 135, 220801, DOI: https://doi.org/10.1103/3hgx-wcdn
Abstract: The precision advantages offered by harnessing the quantum states of sensors can be readily compromised by noise. However, when the noise has a different spatial function than the signal of interest, recent theoretical work shows how the advantage can be maintained and even significantly improved. In this Letter, we experimentally demonstrate the associated sensing protocol, using trapped-ion sensors. An entangled state of multidimensional sensors is created that isolates and optimally detects a signal, while being insensitive to otherwise overwhelming noise fields with different spatial profiles over the sensor locations. The quantum protocol is found to outperform a perfect implementation of the best comparable strategy without sensor entanglement. While our demonstration is carried out for magnetic and electromagnetic fields over a few microns, the technique is readily applicable over arbitrary distances and for arbitrary fields, thus present a promising application for emerging quantum sensor networks.