Differential-thermal analysis around and below the critical temperature Tc of various low-Tc superconductors: A comparative study

摘要

We present specific-heat data on the type-II superconductors V3Si, LuNi2B2Cand NbSe2 which were acquired with a low-temperature thermal analysis (DTA)technique. We compare our data with available literature data on thesesuperconductors. In the first part we show that the DTA technique allows forfast measurements while providing a very high resolution on the temperaturescale. Sharp features in the specific heat such as at the one at the transitionto superconductivity are resolved virtually without instrumental broadening. Inthe second part we investigate the magnetic-field dependence of the specificheats of V3Si and LuNi2B2C at a fixed temperature T=7.5K to demonstrate thatDTA techniques also allow for sufficiently precise measurements of absolutevalues of cp even in the absence of a sharp phase transition. The correspondingdata for V3Si and LuNi2B2C are briefly discussed.