1. Transport Coefficients with WIEN2k
Jorge O. Sofo
Department of Physics
Department of Materials Science and Engineering

3. Thermoelectrics

4. Thermoelectrics

5. Conductivity 101
Drude et al.
k-q q k

6. Conductivity 101 ky kx

7. Conductivity 101

8. Conductivity 2k First Born Approximation Acoustic phonons
Optical phonons (polar, non-polar)
Ionized impurities
Inter-valley scattering …

9. Careful… Doping: rigid band Gap problem
Temperature dependence of the electronic structure.
Alloys. Single site approximations do not work.
Many k-points

10. For free…

11. Application to Thermoelectrics

12. Transport Distribution

13. Application to Thermoelectrics: The best thermoelectric

14. Transport Distribution

22. Bi2Te3

25. Opals Different scattering for phonons and electrons.
Work done for Allied Signal Corp.
Not an alternative… 

26. Summary Tool to explore new compounds, pressure, “negative” pressure.
Prediction of a new compound by G. Madsen.
Easy to expand adding new Scattering Mechanisms
Limited applications to “non-correlated” semiconductors.

27. Collaborators Claudia Ambrosch-Draxl (UNI-GRAZ) Georg Madsen
John Badding (Penn State)
Timo Thonhauser (Wake Forest)
Tom Scheidemantel (Penn State)
With the always present coaching of Jerry Mahan.

29. Bismuth

30. Bi vs. Bi2Te3
Thonhauser, Scheidemantel, Sofo, Appl. Phys. Lett. 2004

31. Why is Bi so good?

32. Is there any hope?