IOS Seminar: Professor Tom Purdy, University of Pittsburgh
Coupling Optical, Mechanical, and Microwave Systems for Quantum Sensing
Event Details
- Date: April 10, 2026
- Time: 1:00 - 2:00 PM
- Location: 4138 Physics Research Building
Abstract
I will present recent experiments that push the limits of hybrid quantum systems in a quest to make better sensors. First, we consider how it might be possible to turn an electro-optic modulator, a workhorse of modern classical telecommunications systems for encoding microwave signals on laser light, into a transducer capable of efficiently moving quantum information between the optical and microwave domains. Our recent results show that bulk, resonant electro-optic devices are capable of near unit transduction efficiency, surpassing even the best nanophotonic devices on this metric. We are currently exploring how laser light in this system can be used to manipulate and measure microwave devices in an analogy to laser cooling in atomic and optomechanical systems. Next, I will explain how the optical lever (one of the oldest and most technically simple precision measurement techniques, with roots in the scientific literature stretching back two centuries and still the go-to readout for modern atomic force microscopes) can be pushed to and beyond standard quantum limits. Despite its simplicity, a few minor modifications to the optical beam path allow optical lever detection to match or even surpass traditional single-mode interferometers in terms of quantum noise and its evasion. If time allows, I will also touch on the unexpected places where acoustic waves can replace their electromagnetic counterparts in quantum sensing: mechanical quantum memories, the acoustic analog of blackbody radiation, and acoustic readout of macroscopic mechanical resonators.
Bio
Dr. Purdy is interested in harnessing the quantum effects intrinsic in the mechanical interaction of light with macroscopic mechanical resonators to improve measurement and metrology. Previously, Dr. Purdy worked as a physicist in the Quantum Optics Group, Quantum Measurement Division, PML at NIST. Before joining NIST, Dr. Purdy has worked on a wide variety of optomechanical systems as a postdoctoral researcher at JILA and in his graduate work at UC Berkeley.