Abstract
Quantum resources can enhance the sensitivity of a device beyond the classical shot noise limit and, as a result, revolutionize the field of metrology through the development of quantum-enhanced sensors. In particular, plasmonic sensors, which are widely used in biological and chemical sensing applications, offer a unique opportunity to bring such an enhancement to real-life devices. Here, we use bright entangled twin beams to enhance the sensitivity of a plasmonic sensor used to measure local changes in the refractive index. We demonstrate a 56% quantum enhancement in the sensitivity of a state-of-the-art plasmonic sensor when compared with the corresponding classical configuration and a 24% quantum enhancement whenp compared to an optimal single-beam classical configuration. We measure sensitivities on the order of 10−10 RIU∕ Hz, nearly 5 orders of magnitude better than previous proof-of-principle implementations of quantum-enhanced plasmonic sensors. These results promise significant enhancements in ultra-trace label-free plasmonic sensing and will find their way into areas ranging from biomedical applications to chemical detection.
| Original language | English |
|---|---|
| Pages (from-to) | 628-633 |
| Number of pages | 6 |
| Journal | Optica |
| Volume | 5 |
| Issue number | 5 |
| DOIs | |
| State | Published - May 20 2018 |
Funding
Acknowledgment. The fabrication of the plasmonic structures was performed at Oak Ridge National Laboratory, operated by UT-Battelle for the U.S. Department of Energy under contract no. DE-AC05-00OR22725. The nanofabrication and electron microscopy were performed at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility.