[Zurück]

H. Michor, E. Scheidt, S. Manalo, M. Müller, E. Bauer, G. Hilscher:
"Superconductivity in layered YB₂C₂";
Journal of Physics: Conference Series, 150 (2009), S. 052160-1 - 052160-4.

Superconductivity in the layered yttrium diboride dicarbide, YB2C2, has been revisited by means of specific heat, magnetic susceptibility and resistivity measurements down to 50 mK revealing a bulk superconducting transition at 1.0 K. Analysing the low temperature specific heat we obtain a Sommerfeld coefficient of the normal state electonic contribution, γ = 3.1(1) mJ/molK2, and a Debye temperature, ΘDLT = 680(10) K. The specific heat anomaly at Tc, ΔC approxeq 4.5mJ/mol K, thus, yields a thermodynamic ratio ΔC/γTc - 1.4 in close agreement with the BCS value. For polycrystalline Y11B2C2 prepared by inductive melting we observe a pronounced resistive anomaly near 3.6 K which, however, corresponds to a rather spurious specific heat anomaly and is thus attributed to traces of YC2 present in this sample.

http://dx.doi.org/10.1088/1742-6596/150/5/052160

http://dx.doi.org/10.1088/1742-6596/150/5/052160