Alberto M. Marino, a physicist at The University of Oklahoma, is collaborating with Raphael Pooser at the U.S. Department of Energy’s Oak Ridge National Laboratory to develop quantum-enhanced sensors. In a recent study, they were able to demonstrate the ability of quantum states of light to enhance the sensitivities of state-of-the-art plasmonic sensors.
Plasmonic sensors are currently used in a number of applications, such as biosensing, atmospheric monitoring, ultrasound diagnostics, and chemical detection. The sensitivity of the sensors is limited by the ‘shot noise’ – the variance of photon collection rates over intervals of time. But, when interfaced with quantum states of light that exhibit reduced noise properties, the noise floor can be reduced below the classical shot noise limit. This makes it possible to obtain a quantum-based enhancement of the sensitivity of the sensor. Experimentation involved the use of bright entangled twin beams to enhance the sensitivity of a plasmonic sensor used to measure local changes in refractive index. They were able to demonstrate a 56% quantum enhancement in the sensitivity of state-of-the-art plasmonic sensor.
“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,” said Marino, a professor in the Homer L. Dodge Department of Physics and Astronomy, OU College of Arts and Sciences. “In particular, plasmonic sensors offer a unique opportunity to enhance real-life devices.”
A study on this project, “Quantum-Enhanced Plasmonic Sensing,” has been published in the scientific journal Optica.