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Measurement of the superconducting energy gap in La-Ba-Cu oxide and La-Sr-Cu oxide

Published

Author(s)

Stephen E. Russek, P. E. Sulewski, A.J. Sievers, H. D. Hallen, D. K. Lathrop, R A. Buhrman

Abstract

We report on far-infared (FIR) reflectivity measurements on sintered pressed poweder samples of La-Ba-Cu oxide and La-Sr-Cu oxide. THe best samples show fairly sharp transitions to zero measurable resistance with a transition midpoint of 28 K for the Ba alloy and 36 K for the Sr alloy. The FIR measurements reveal an energy gap below Tc with, depending on the measurement criterion used, values of 2delta/kbTc of 1.3-1.95 for La-Ba-Cu oxide and 1.6-2.7 for La-Sr-Cu oxide, which are lower than expected for a BCS superconductor.
Citation
Physical Review B
Volume
35

Citation

Russek, S. , Sulewski, P. , Sievers, A. , Hallen, H. , Lathrop, D. and Buhrman, R. (1987), Measurement of the superconducting energy gap in La-Ba-Cu oxide and La-Sr-Cu oxide, Physical Review B, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=905792 (Accessed October 9, 2025)

Issues

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Created April 1, 1987, Updated February 19, 2017
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