Meet Liuyan Zhao

Liuyan Zhao, PhD, is Assistant Professor of Physics at University of Michigan.

Zhao is an experimental condensed matter physics scientist. Her research group searches for new states in materials. These new states occur at the electron level, and can be observed in unique magnetic properties.

Zhao Research Group

How do you make a new discovery that’s never been observed, or we never knew existed before?

Zhao Research Group investigates the symmetry, time, and spatial properties of materials and elements using lasers. These measurements help them look for new states at the electron level, which are observed in unique magnetic properties.

Discovering these new magnetic properties may be the key to unlocking future technologies in computer sciences and data processing. Or, it might just be a new piece in the puzzle to completing fundamental quantum physics theories.

Lasers and Optics

Using a technique called rotational anisotropy-second harmonic generation, or RA-SHG, Zhao’s lab measures laser light that is reflected off of the material (the SHG signal) with a photon-sensitive camera. These sensitive cameras take up to one minute to record one pixel of an image, at the scale of 200 microns.

RA-SHG scan data helps researchers create a map and pinpoint areas of the material to do further experiments. This includes looking at symmetrical properties, how properties change in extreme temperatures, or changes through time.

Samples

The materials Zhao’s lab studies are not typically found in nature. They can be 3D samples that are very small or 2D samples that are as thin as a single atom. After preparation, the samples are ready for measurement of their properties with laser light, or to see how they react in extreme low temperatures.

Youngjun Ahn is a postdoctoral research fellow and Hongchao Xie is a postdoctoral scholar at the University of Michigan.

Data Collection

Zhao’s lab uses a technique called rotational anisotropy-second harmonic generation, or RA-SHG. Laser light is directed onto the sample material and its properties are then observed by measuring light (the SHG signal) that reflects off of it.

Xiaoyu Guo is a graduate student in the Zhao Research Group.

Measurements through Time

Time-resolved RA-SHG (Tr-RA-SHG) uses multiple laser pulses to make measurements through time. Using this technique, the Zhao Research Group can see how a sample’s properties may change through time.

Rachel Owen is a graduate student in the Department of Physics at University of Michigan.

A New Discovery

The Zhao Research Group was the first to observe a ferro-rotational moment. This phenomenon had never been directly observed before, but had been theorized in quantum physics. The result was achieved using RA-SHG techniques with the material RbFe(MoO4)2 in extremely low temperatures.

Elizabeth Drueke is a graduate student in the Department of Physics at University of Michigan.