Harold T. Stokes
B.S. in physics, Brigham Young University, 1971
Ph.D. in physics, University of Utah, 1977
1977-1978, Post-Doctoral Fellow at University of Utah
1978-1981, Post-Doctoral Fellow at University of Illinois at Champaign-Urbana
1981-present, Faculty at Brigham Young University
Links to course home pages:
Teaching resources which I and my colleagues
have developed for the courses I teach:
Textbooks which I
have written for solid state physics courses.
Current research interests
Phase transitions in solids
I have been collaborating with Professor Dorian M. Hatch since 1983 on
this project. We have been applying group-theoretical methods to the study
of transitions between crystalline phases in solids. One of the major successes
of our work has been the establishment of a large data base and the implementation
of computer algorithms to carry out the group-theoretical computations
in a wide variety of cases. (Click here
for information about downloading this software.)
Our collaboration has resulted in 28 jointly-authored
papers in refereed journals over the last fourteen years .
In addition, we published a major reference work, Isotropy Subgroups
of the 230 Crystallographic Space Groups, and played a major role in
preparing the 1993 English edition of the Russian reference work, Representations
of the Crystallographic Space Groups, by O. V. Kovalev.
Most recently, we have been collaborating with Dr. G. M. Chechin and
Dr. V. P. Sakhnenko at the Rostov State University in Rostov-on-Don, Russia.
They developed a group-theoretical method for treating non-linear oscillations
of atoms in crystals. We are implementing some of their ideas on computer.
First-principles calculations in solids
I spent the 1993-94 academic year on professional leave at the Naval Research
Laboratory in Washington, D.C. I collaborated with Dr. Larry Boyer in developing
computer software for implementing a new type of first-principles energy
calculation in crystalline solids. "First principles" means no adjustable
parameters. Such calculations are used to determine various properties
of materials, such as crystalline structure, elastic constants, vibrational
spectra, and phase diagrams, all from first principles with no adjustable
parameters. Of course, we have a long way to go before such calculations
can produce quick, accurate results. I am continuing the development of
these methods here at BYU on a Hewlett Packard workstation (700 series).
Papers and Talks
Papers published in refereed journals
Invited papers at scientific meetings
Contributed papers at scientific meetings