2001/12/05 by J. L. Luo, Jiaming Luo, Luo, J. L. +8
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #Strongly Correlated Electrons (cond-mat.str-el) #Superconductivity (cond-mat.supr-con) #Theoretical and Computational Physics #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.cond-mat/0112065
7 pages, 10 figures
arxiv created 2001/12/05 · openalex publication_date 2001/12/05 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We have measured the electronic specific heat of Y0.8Ca0.2Ba2Cu3O7-δ using a high-resolution differential technique from liquid helium temperature to room temperature in an applied magnetic field up to 13T. The field dependence of the electronic specific heat at low temperatures in the superconducting state behaves differently in the overdoped and underdoped regimes, varing as √(H) in the overdoped regime but as H in the underdoped regime. An entropy loss is observed in the normal state in optimal and underdoped samples, which can be attributed to the opening of a normal state psuedogap. From the temperature and field dependences of the free energy, the temperature dependence of the upper critical field Hc2 is determined. For the overdoped sample (x=0.79), we find Hc2 to have a negative curvature.