Modeling Materials for Solar Energy Capture and Conversion: Using Density Matrix and Abinitio Electr

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Modeling Materials for Solar Energy Capture and
ConversionUsing Density Matrix and Ab-initio
Electronic Structure Methods 1

• David A. Micha 2
• Dr. Dmitri Kilin, Andrew Leathers, Jessica
  Ramirez, Chris Obara, David Arlund, Andy Rosenbaum

• Work supported by the National Science Foundation
  and the Dreyfus Foundation
• Office at NPB 2318 tel. [phone]
  micha_at_qtp.ufl.edu

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Motivation
On the science

• Develop new theory at the interface of Physics,
  Chemistry, and Applied Math
• Develop computational tools for modeling of
  surface properties
• Discover new materials for photovoltaics

On its applications

• Use sunlight to produce electricity and fuel
• Contribute to environmental protection
• Contribute to national security

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Physical systems and properties

• Nanostructured surfaces, with adsorbed atomic
  clusters and molecular dyes (E.g. AgNSi(111)H)
• Doped semiconductors and insulators (Si, TiO2,
  MgO, )
• Nanosized particles of semiconductors (Si, CdTe,
  CdS, )

• Optical properties photovoltages, dynamical
  absorption coefficient
• Rates of exciton diffusion
• Rates of electron transfer creation of e-h
  pairs
• Electronic conductivity through interfaces and
  between nanoparticles

• First generation photocells from crystalline Si
• Second generation photocells from particle
  deposition on plastic films
• Third generation photocells from multilayer
  systems and from nanoparticle
• aggregates

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Theory and computation
Density matrix theory

• Treatments combining quantum mechanics and
  statistical mechanics
• Treatments accounting for properties of a
  primary region in a medium
• Derivation of equations of motion for reduced
  density matrices (RDMs)

Ab initio electronic structure calculations

• Using density functional theory (DFT) and time
  dependent DFT (Gaussian 03)
• Using DFT for solids including atom dynamics and
  electronic couplings (VASP)

Computation of the density matrix

• Solving coupled integrodifferential equations
  for the RDM
• Accounting for time evolution of quantum state
  populations and coherences
• Quantum dissipative dynamics including
  fluctuation and dissipation phenomena

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Interested in research?

• You can see some details in www.qtp.ufl.edu/mich
  a
• You are welcome to come by my office at 2318 NPB
  for more information
• I would add to my research group one or two
  undergraduate students
• with the right motivation, knowledge and time,
  starting this coming Spring
• 2009 semester
• My Dreyfus Foundation grant would cover some of
  the tuition fees in the
• Summer term, and assistant support for a
  student with dedicated
• time for research work.