Low temperature specific heat has been measured for an overdoped La2−xSrxCuO4 (x = 0.22) single crystal. The quasiparticle density of states (DOS) in the mixed state is found to deviate from the predicted scaling law Cvol=Hf(T/H1/2). However, this scaling behavior is nicely reconciled if one considers the normal core region (ξ≈ 21A˚) which gives small contribution to the total DOS. The radius of the core and other parameters derived are consistent with reported values. Our results suggest that there is no zero-bias conductance peak (ZBCP), which is predicted by the simple Bogoliubov de-Gennes theory in the vortex core of a d-wave superconductor.
@article{arxiv.cond-mat/0301366,
title = {Core Size Effect on the Vortex Quasiparticle Excitations in Overdoped $La_{2-x}Sr_xCuO_4$ Single Crystals},
author = {Z. Y. Liu and H. H. Wen and T. Xiang and Seiki Komiya and X. F. Sun and Yoichi Ando},
journal= {arXiv preprint arXiv:cond-mat/0301366},
year = {2007}
}