Lab Home | Phone | Search
Center for Nonlinear Studies  Center for Nonlinear Studies
 Home 
 People 
 Current 
 Executive Committee 
 Postdocs 
 Visitors 
 Students 
 Research 
 Publications 
 Conferences 
 Workshops 
 Sponsorship 
 Talks 
 Seminars 
 Postdoc Seminars Archive 
 Quantum Lunch 
 Quantum Lunch Archive 
 P/T Colloquia 
 Archive 
 Ulam Scholar 
 
 Postdoc Nominations 
 Student Requests 
 Student Program 
 Visitor Requests 
 Description 
 Past Visitors 
 Services 
 General 
 
 History of CNLS 
 
 Maps, Directions 
 CNLS Office 
 T-Division 
 LANL 
 
Thursday, July 03, 2014
3:00 PM - 4:00 PM
MPA-CMMS Conference Room, TA-3, Bldg 32, Rm 134

CMS Colloquium

Specific Heat of Iron Based Superconductors at Tc - A Global Correlation

Greg Stewart
University of Florida

In the study of the new iron based superconductors, there are not many global correlations. For example, the early statement that Tc is a maximum (in the 1111 materials) when the As-Fe-As bond angle is the 'regular' tetrahedron value of 109.47 degrees has not been borne out in, e. g., the 111 LiFeAs. However, one correlation pointed out by Bud'ko, Ni and Canfield (Phys. Rev. B 79, 220516 (2009)) based on samples of the 122 iron based superconductors has since (Kim et al., J. Phys.: Conds. Mat. 23, 222201 (2011)) been confirmed in both the 111 and the 11 iron based superconductors. This correlation concerns the discontinuity, deltaC, at the superconducting transition temperature and its dependence on Tc. More recent data, and a comparison of this iron based superconductor behavior with BCS superconductors, will be given. This correlation keeps on being borne out and serves as a.) a metric for sample quality; b.) a test whether a newly discovered iron-containing superconductor is of the same class of superconductor as the other known iron based superconductors and c.) a challenge to theorists to explain this behavior.

Host: Joe Thompson