Atomic Scale Materials

My group is in the physics department at the University of Arizona. Our research is focused on studying low-dimensional systems using a combination of scanning probe microscopy, optical spectroscopy and electrical transport measurements.  Currently, we are investigating atomic scale systems ranging from graphene and transition metal dichalcogenides to carbon nanotubes.

Graphene is a unique system because of its two-dimensional structure as well as linear dispersion relation. This dispersion relation causes the electrons to behave as massless particles, Dirac fermions, with an effective speed of light that is about 300 times slower than in light in vacuum. The two-dimensional structure of graphene makes it ideal to study with scanning probe microscopy because all of the atoms lie at the surface. We are investigating ways to probe and control the electronic properties of graphene using low temperature scanning probe microscopy and Raman spectroscopy.

Transition metal dichalcogenides have a similar structure to graphene yet can host a much wider variety of physical phenomena ranging from semiconducting behavior to superconducting and charge density waves. Using spatially resolved imaging techniques, we are exploring some of the unique properties of these materials such as the spin-valley-layer coupling in the semiconducting compounds.

The one-dimensional nature of carbon nanotubes means that interaction effects are very important for their electronic and optical properties. This leads to phenomena ranging from Luttinger liquid behavior to strong exciton binding. Scanning probe microscopy provides extremely high-resolution information about the local density of states in these materials providing insight into these interactions.

I am also a member of the Chemical Physics program and an associate editor of APL Materials.

If you are interested in joining the group as a post-doc, Ph.D. student or undergraduate please contact me.