John Papanikolas

John Papanikolas

Professor

   Caudill Laboratories 118
   919-962-1619
   john_papanikolas@unc.edu
  Group Website
    Curriculum Vitae


Research Interests

Ultrafast Spectroscopy, Ultrafast Microscopy, Solar Energy Conversion


Professional Background

Bowdoin College, B.A., 1987; University of Colorado-Boulder, Ph.D., 1994. Postdoctoral Associate, University of Colorado-Boulder, 1994-1997


Research Synopsis

Research in my group is directed at the characterization of complex chemical systems using femtosecond laser spectroscopy. Projects in my group fall into two main themes. The first theme focuses on characterizing the fundamental processes that underpin solar energy conversion. Here we use a combination of ultrafast spectroscopic and computer simulation methods to follow excited state energy transport in light-harvesting molecular assemblies. We are also interested in the charge separation event that occurs following photoexcitation of molecular chromophores surfaces. The second theme is aimed at combining ultrafast spectroscopy with optical microscopy to visualize the charge carrier dynamics in semiconductor nanowires, nanowire networks and nanoscale devices. Recently we have used a spatially separated method developed in our group that can excited a structure in on location and probe it in another, enabling us to visualize the motion of electrons within a single structure. The ultrafast spectroscopic experiments are augmented with computer modeling, for example Monte Carlo, Molecular Dynamics simulations and Finite-Difference methods, to provide a detailed picture of the underlying physical phenomena.

News & Publications

Imaging Silicon Nanowires

Researchers in the Papanikolas and Cahoon groups have developed a pump–probe microscope capable of...

 

Strain-Induced Changes

Strain-induced changes to the electronic structure of nanoscale materials provide a promising avenue for expanding the...