Research

Broadly speaking, we are currently interested in problems involving

1. electronic excitations, optical properties, and lumiescence, all via ab initio approaches
2. properties of nanostructures, especially nanowires and nanotubes
3. the physics of transition metal oxides and their interfaces (as part of CRISP.)
4. organic/inorganic interfaces for nanoscale photovoltaics applications

Here is a glimpse of current topics:

• Electron excitation, optical response, and photoluminescence
  • Solid-state defects: e.g. bulk silica
  • carbon nanotubes
  • molecules
  • GaN nanotubes and nanowires
• Nanostructures
  • Boron nanotubes and 2D sheets: structure, electronic states, conductivity, etc.
  • Metal-doped boron nanostructures
  • GaN nanotubes
  • Carbon nanotubes
• Surfaces and epitaxial interfaces (atomically sharp, coherent and abrupt interfaces between two materials)
  • Dynamics, thermodynamics, and growth of transition metal oxides on semiconductors
  • Interface structure and function of transition metal oxides on semiconductors: e.g. BaO and SrTiO₃ on Si, BaTiO₃ on Ge
  • Engineered oxide/semiconductor interfaces to create ferroelectricity, magnetism, metal-insulator transitions, etc.
  • Oxide-oxide interfaces: novel phenomena such as those seen at SrTiO₃ / LaAlO₃, La_1-xSr_xMnO₃/SrTiO₃, ferroelectric/La_1-xSr_xMnO₃ interfaces including 2D electron gases, dynamic cross-interface phonon coupling, magneto-electric couplings, orbital ordering, etc.
  • Switchable chemistry and catalysis on ferroelectric surfaces
• Ab initio Green's function methods for dealing with electron correlations, e.g. in complex oxides
• Organic/inorganic interfaces for photovoltaics: covalently bonded P3HT/ZnO and P3HT/carbon nanotube junctions