A single photon can reveal whether a neuron is firing or failing, by exploiting a quantum trick where two photons bunch together when they hit a beamsplitter. This project tackles a fundamental gap: although quantum optics is well understood in theory, no one has yet turned its most sensitive effects—like photon bunching and Boson sampling—into practical tools for imaging living biological tissue. Current techniques struggle to see deep into scattering brain tissue or to track neuron activity at the sub-picosecond timescales where degeneration begins. The researchers will build a new kind of imaging system that uses many-photon quantum states to detect tiny changes in the path of light passing through neurons. If it works, the technique could map neuron activity with orders-of-magnitude better resolution than existing methods, and track structural changes in the brain caused by neurodegeneration across large spatial scales. This is fundamental science at the interface of quantum optics and biology. There is no immediate clinical application. But if successful, it could eventually give neuroscientists a way to watch the earliest signs of diseases like Alzheimer’s unfold in real time—something no current microscope or scanner can do.
View original technical description
The basic nature of quantum states of light and their detection is largely well established and understood. Consequently, several sensing and imaging schemes based on quantum states of light have been proposed over the years, ranging from ghost imaging to quantum optical coherence tomography. However, the challenge still remains to demonstrate and fully exploit possible quantum advantages in important application areas such as bio-imaging and medical imaging. By working at the interface between quantum optics, information theory and computational imaging, we will develop many-photon correlation imaging and Boson sampling into new techniques for imaging and will then tackle important problems related to bio and medical imaging applied to neuron activity and degeneration with unprecedented precision. The underlying physical mechanism we will harness is photon coalescence or bunching, a quantum effect whereby two photons bunch together when they overlap at a beamsplitter. These measurements allow one to perform very precise detection of small changes in the path of the one of the two photons. We will carry this concept forward and develop enhanced imaging at large depths of neuron density and imaging of fluorescence lifetimes at the sub-picosecond scale with orders of magnitude enhancement in the resolution of neuron activity. Similar and even richer photon bunching effects take also place in complex media made of, for example, scattering defects that act as beamsplitters. We will employ multi-photon states, in a very similar fashion to recent quantum computers that rely on Boson Sampling: here the biological system, e.g. a collection of neurons, act as the complex Boson sampling medium, a quantum biological computer of sorts. Boson sampling will be used to detect and track progression over large spatial scales of structural changes in the brain due to neurodegeneration.
Plain English summaries and category classifications on this site are generated by AI and may not perfectly reflect the original research.
Is something wrong? Let us know