Photonic quantum technologies for brain science
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Lecturer: Daniele Faccio - Royal Academy of Engineering Chair in Emerging Technologies School of Physics & Astronomy, Director of Research Advanced Research Centre (ARC), University of Glasgow, UK
Date: March 28, 2025 11:30 a.m. - 1 p.m.
Location: Querzoli

State of the art optical imaging delivers extraordinarily detailed images that range from nanometer-scale resolution to non-invasively sensing brain activity. However, there are still technical capabilities that sit at the limit or beyond what classical imaging can do. I will give an overview of some basic quantum-enabled capabilities for sensing and imaging and their applications in various domains, with a focus on neuro-imaging. 

Single photon cameras can have very high temporal resolution and very high frame rates. This provides the opportunity for fluorescence lifetime imaging at unprecedented pixel resolution and frame rates for real time imaging of transient processes in biology such as Calcium or action potential waves in cardiomyocyte assays or neurons.

If we instead consider the light source – entangled photons provide the ability to probe the dynamics of photosensitive processes. When probing photo-activated biology or chemical processes, one must question whether the light source itself is affecting the dynamics under study. We show as an example, LH2-LH1 energy transfer dynamics in photosynthetic purple bacteria as a stepping stone before looking at light sensitive molecules found in the eye.

At the macroscopic scale, single photon technologies can be used to detect brain activation patterns. Despite the use of light to measure haemodynamic response in the brain since the 1980’s, it is still unclear exactly how light propagates through the head and if light can reach sub-cortical deeper regions. We show experimental results indicating that it is possible to transmit light diametrically through the human head. A detailed numerical study reveals that light is guided around the head via a newly discovered diffusion-based guiding mechanism that then has implications for light guiding also at the neuron-scale. This connection between the micro (neuron) and macro (whole brain) scales is currently being investigated for the delivery of light deep into the brain for diagnostics and treatment of brain disorders.