TY - JOUR
T1 - Magnetic-field-induced enhancement of the vortex pinning in the overdoped regime of La 2-xSr xCuO 4
T2 - Relation to the microscopic phase separation
AU - Tanabe, Yoichi
AU - Adachi, Tadashi
AU - Omori, Keisuke
AU - Sato, Hidetaka
AU - Noji, Takashi
AU - Koike, Yoji
PY - 2007/11
Y1 - 2007/11
N2 - In order to investigate the inhomogeneity of the superconducting (SC) state in the overdoped high-T c-cuprates, we have measured the magnetic susceptibility, χ, of La 2-x,Sr xCuO 4 (LSCO) single crystals in the overdoped regime in magnetic fields parallel to the c-axis up to 7 T on warming after zero-field cooling. It has been found for x = 0.198 and 0.219 that the temperature dependence of χ in 1 T shows a plateau, that is, χ is almost independent of temperature in a moderate temperature-range in the SC state. Moreover, a so-called second peak in the magnetization curve has markedly appeared in these crystals. These results indicate an anomalous enhancement of the vortex pinning and strongly suggest the occurrence of a microscopic phase separation into SC and normal-state regions in the overdoped high-T c cuprates.
AB - In order to investigate the inhomogeneity of the superconducting (SC) state in the overdoped high-T c-cuprates, we have measured the magnetic susceptibility, χ, of La 2-x,Sr xCuO 4 (LSCO) single crystals in the overdoped regime in magnetic fields parallel to the c-axis up to 7 T on warming after zero-field cooling. It has been found for x = 0.198 and 0.219 that the temperature dependence of χ in 1 T shows a plateau, that is, χ is almost independent of temperature in a moderate temperature-range in the SC state. Moreover, a so-called second peak in the magnetization curve has markedly appeared in these crystals. These results indicate an anomalous enhancement of the vortex pinning and strongly suggest the occurrence of a microscopic phase separation into SC and normal-state regions in the overdoped high-T c cuprates.
KW - La Sr CuO
KW - Magnetic susceptibility
KW - Phase separation
KW - Second-peak effect
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U2 - 10.1143/JPSJ.76.113706
DO - 10.1143/JPSJ.76.113706
M3 - Article
AN - SCOPUS:36148937552
VL - 76
JO - Journal of the Physical Society of Japan
JF - Journal of the Physical Society of Japan
SN - 0031-9015
IS - 11
M1 - 113706
ER -