--------------------------------------------------------------------
   COLLOQUIUM OF THE LABORATORY FOR COMPUTER DESIGN OF MATERIALS        
        Institute for Computational Sciences and Informatics	
                           (CSI 898-Sec 001) 
--------------------------------------------------------------------

 Computation of Optical Properties for Quantized Electronic Systems


                         Verne L. Jacobs
             Center for Computational Materials Science
            Naval Research Laboratory, Washington, D. C.

A density-matrix description has been developed to treat relaxation (decoherence)
phenomena during resonant and non-resonant radiative transitions of quantized
electronic systems, including many-electron atoms and quantum-confinement systems
(e. g., semiconductor microstructures). Radiative and collisional relaxation
phenomena have been treated using Liouville-space projection-operator techniques.
Both time-independent (resolvent-operator) and time-dependent (equation-of-motion)
formulations have been developed. The self-energy operators that occur in these
formulations can provide the fundamental basis for a self-consistent determination
of the non-equilibrium and coherent electronic-state kinetics together with the
homogeneous spectral-line shapes. This density-matrix description can be adapted
for the computer simulation of electromagnetic processes. From first-principles
electronic-structure calculations or from semi-empirical approaches, the
parameters describing the elementary collisional and radiative interactions can be
evaluated and organized into the basic data set for the application of the
density-matrix description. The final product is a theoretical prediction for the
linear or non-linear optical absorption or emission spectrum corresponding to a
given set of values for the appropriate physical variables, such as temperatures,
densities, and electric or magnetic field strengths.

                          Monday , April 3, 2000
                                  4:30 pm
                        Room 206, Science & Tech. I

Refreshments will be served.
----------------------------------------------------------------------
Find the schedule at http://csi.gmu.edu/lcdm/seminar/schedule.html