With Air Force Grant, Physicist Will Shed Light On an Emerging Field in Physics

Bo Zhen, Assistant Professor of Physics and Astronomy and Elliman Faculty Fellow, has been awarded a Young Investigator Grant from the Air Force Office of Scientific Research. Zhen will receive $450,000 for a three-year period to investigate non-Hermitian topological photonics.

In the past decade, topology, a branch of the mathematics studying the preserved properties of objects under continuous deformations, has received an increasing amount of attention in physics. From a topological point of view, a coffee mug and a donut are the same. Since each object has one hole, it is possible for the donut to morph into a mug through continuous deformations: one would simply make a depression into one side of the donut to make the mug and shrink the donut's hole to make the mug's handle. This sort of abstraction, Zhen says, gives way to new properties in physics and interesting applications in practice.

“When we tie our shoelaces in the morning, it's never perfect,” he says. “It's not one particular shape and we don't need to measure the exact dimensions. It’s the topology of the knot that really matters.”

Although the understanding of this new concept first started in electronic systems through the study of the topological phases of electrons, negatively charged subatomic particles, Zhen’s research focuses on photons, particles of light.

One application for this, Zhen says, is improving chemical or biological sensors to allow them to reach much higher sensitivities so they can detect tiny changes, sometime even down to a single particle, in the environment. These sensors can be used to monitor the level of glucose in blood, determine drug residue in blood or detect the level of poisonous elements in water.