RESEARCH INTERESTS OF G. R. STEWART
Iron Pnictide Superconductors:
With the discovery of superconductivity up to Tc=57 K
(fueled by the Hosono group's discovery of superconductivity at 26 K in
LaFeAsO doped with F), a number of interesting physical questions have
been raised. Chief among these are: What other compounds
with perhaps even higher transition temperature can be found?
What role do non-conventional pairing mechanisms (including spin
fluctuations) play in the superconductivity?
We are investigating both known, and as-yet
uninvestigated compounds (there are over 800 known systems in the
'1111' structure (like LaFeAsO) and the '122' structure (based on
BaFe2As2)). In addition, specific heat as a function of angle and
field up to 20 Tesla and down to 0.1 K are either under investigation
or being planned.
Our group is involved in a number of ongoing, active
collaborations, including research groups in Kyoto University, Los Alamos
National Laboratory, and (starting in 2008) Seoul National