Mohamed Elkabbash, Wyant College of Optical Sciences, UA
When
Where
Abstract:
This talk will explore how fundamental physics and practical technology meet in my research, spanning nanoscale gravity, statistical signal detection, advanced imaging, and photonic computing. I will begin with our proposal for measuring gravitational interactions between trapped nanoparticles, where we employ resonant modulation of optical tweezers to amplify tiny displacements. Because the signal is buried in highly correlated noise, we are developing new approaches beyond standard averaging, including modified lock-in techniques and a generalized likelihood ratio test (GLRT).
Building on this framework, we extended GLRT to thermal imaging problems under extremely low signal-to-noise conditions. Our implementation allows the detection and tracking of objects such as drones, extracting parameters including position, velocity, and temperature. This method outperforms neural networks in accuracy and computational efficiency. We have also introduced a sequential parameter estimation approach, which accelerates estimation by two orders of magnitude relative to maximum-likelihood methods while requiring fewer detection resources. This computational approach to image through scattering media including biomedical and space imaging.
On the other hand, imaging through scattering media can be performed using programmable photonics. Here, my group is developing high-speed spatial light modulators (SLMs) with the goal of pushing liquid crystal SLMs at least two orders of magnitude beyond their present speed limits. Such devices would enable real-time imaging through complex media, such as living tissues, and open new possibilities in photonic computing.
In this context, I will describe our efforts in optical matrix–vector multiplication using thin-film coatings, a platform that scales more effectively than integrated photonics while maintaining low power overhead.
Finally, I will present our proposal for an integrated photonic circuit in which proper-time differences arising from rotation in an on-chip Sagnac interferometer could act as a source of decoherence. This system offers a new way to experimentally probe the overlap between quantum mechanics and general relativity.
3:00 PM in PAS 201 / Zoom Meeting
Refreshments in PAS 236, 2:30PM