We present electronic transport measurements of a single wall carbon nanotubequantum dot coupled to Nb superconducting contacts. For temperatures comparableto the superconducting gap peculiar transport features are observed inside theCoulomb blockade and superconducting energy gap regions. The observedtemperature dependence can be explained in terms of sequential tunnelingprocesses involving thermally excited quasiparticles. In particular, these newchannels give rise to two unusual conductance peaks at zero bias in thevicinity of the charge degeneracy point and allow to determine the degeneracyof the ground states involved in transport. The measurements are in goodagreement with model calculations.
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