2001/04/18 by D. Matthey, Stefano Gariglio, S. Gariglio +3
Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic properties of thin films #Physics of Superconductivity and Magnetism #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.64.024513
6 pages, 4 figures, RevTEX, to appear in Phys. Rev. B
arxiv created 2001/04/18 · openalex publication_date 2001/06/19 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01
We report on measurements of the resistivity and Hall coefficient in underdoped GdBa2Cu3O_7\ensuremath-\ensuremathδ epitaxial thin films grown by off-axis magnetron sputtering. The films have been lithographically patterned allowing precise measurements of the temperature dependencies of the inverse Hall constant RH^\ensuremath-1 and of the Hall angle \ensuremathθH. We find that RH^\ensuremath-1 is linear in temperature between 300 K and the pseudogap temperature T*, whereas cot(\ensuremathθH) displays a perfect T2 temperature dependence typically between 300 and 100 K. We observe for all the samples that the temperature at which the temperature dependence of cot(\ensuremathθH) deviates from the T2 behavior is correlated to the temperature at which RH displays a peak. This characteristic temperature, found to lie between Tc and T*, does not depend markedly on the doping level and defines a crossover line in the temperature versus doping phase diagram. We tentatively relate these findings to recent high-frequency conductivity and Nernst effect experimental results, and we briefly discuss the possible consequences for competing theories for the pseudogap state of the cuprates.