High-resolution measurements of the thermal expansion of superconducting Co-doped BaFe2As2

Journal Article · Thu Jan 01 00:00:00 EST 2009 · Physical Review B

DOI:https://doi.org/10.1103/PhysRevB.79.214505· OSTI ID:961795

Luz, M. S. ^[1]; Neumeier, J. J. ^[1]; Bollinger, R. K. ^[1]; Sefat, A. S. ^[2]; McGuire, Michael A ^[3]; Jin, R. ^[4]; Sales, Brian C ^[3]; Mandrus, David ^[3]

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1. Montana State University
2. Oak Ridge National Laboratory (ORNL)
3. ORNL
4. University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL)

High-resolution thermal expansion measurements of single crystalline BaFe{sub 1.84}Co{sub 0.16}As{sub 2} and BaFe{sub 1.77}Co{sub 0.23}As{sub 2} in the temperature range 5 < T < 300 K are reported. The thermal expansion is highly anisotropic, with the largest expansion along the c axis. Distinct anomalies are present at the normal-to-superconducting phase-transition temperature T{sub c}; the phase transition appears to be continuous. No structural transitions are observed over the temperature range of our measurements. The thermal expansion data and heat-capacity data acquired on the same specimens are used to estimate the volumetric pressure derivative of T{sub c} using the Ehrenfest relation.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 961795
• Journal Information: Physical Review B, Vol. 79, Issue 21; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM COMPOUNDS
COBALT ADDITIONS
IRON ARSENIDES
MONOCRYSTALS
PHASE TRANSFORMATIONS
SPECIFIC HEAT
TEMPERATURE RANGE
THERMAL EXPANSION
TRANSITION TEMPERATURE