TY - JOUR
T1 - Anisotropic properties of the anomalous second peak in the magnetization curves and the irreversibility field of YBa2Cu3Oy (6.6 ≤ y ≤ 6.9) single crystals
AU - Kobayashi, N.
AU - Hirano, K.
AU - Nishizaki, T.
AU - Iwasaki, H.
AU - Sasaki, T.
AU - Awaji, S.
AU - Watanabe, K.
AU - Asaoka, H.
AU - Takei, H.
N1 - Funding Information:
The authors would like to acknowledge M. Tachiki and H. Matsumoto for their helpful discussions. We also would like to thank T. Otomo, H. Miura, S. Tanno, Y. Ishigami and K. Hosokura for adequate supplying of liquid helium and T. Sato for preparing the manuscript. This work was supported by a Grant-in-Aid for Scientific Research on Priority Areas, "Science of High-Tc Superconductivity" from the ministry of Education, Science and Culture, Japan.
PY - 1995/9/15
Y1 - 1995/9/15
N2 - Anisotropic properties of the anomalous second peak in the magnetization curves and the irreversibility field have been investigated by magnetic measurement for YBa2Cu3O7 (6.6 ≤ y ≤ 6.9) single crystals in magnetic fields up to 55 kOe. The angular dependence of the magnetic field Hp at which the second peak appears is well described by the Ginzburg-Landau effective-mass model. This behavior results from the anisotropic vortex structure dominated by the effective mass of superconducting electrons. However, the anisotropic behavior of the irreversibility field Hirr is given by an extended expression, Hirr ln Hirr ∞ 1/(cos2θ + γ-2sin2θ) 1 2, which is proposed by taking account of the influence of the flux creep on the irreversibility field. The anisotropic parameter γ is consistently estimated from the angular dependence of both characteristic fields of Hp and Hirr. The γ value increases with decreasing oxygen content indicating the suppression of the interlayer coupling between CuO2 superconducting layers by reducing oxygen.
AB - Anisotropic properties of the anomalous second peak in the magnetization curves and the irreversibility field have been investigated by magnetic measurement for YBa2Cu3O7 (6.6 ≤ y ≤ 6.9) single crystals in magnetic fields up to 55 kOe. The angular dependence of the magnetic field Hp at which the second peak appears is well described by the Ginzburg-Landau effective-mass model. This behavior results from the anisotropic vortex structure dominated by the effective mass of superconducting electrons. However, the anisotropic behavior of the irreversibility field Hirr is given by an extended expression, Hirr ln Hirr ∞ 1/(cos2θ + γ-2sin2θ) 1 2, which is proposed by taking account of the influence of the flux creep on the irreversibility field. The anisotropic parameter γ is consistently estimated from the angular dependence of both characteristic fields of Hp and Hirr. The γ value increases with decreasing oxygen content indicating the suppression of the interlayer coupling between CuO2 superconducting layers by reducing oxygen.
UR - http://www.scopus.com/inward/record.url?scp=0029377280&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0029377280&partnerID=8YFLogxK
U2 - 10.1016/0921-4534(95)00393-2
DO - 10.1016/0921-4534(95)00393-2
M3 - Article
AN - SCOPUS:0029377280
SN - 0921-4534
VL - 251
SP - 255
EP - 262
JO - Physica C: Superconductivity and its Applications
JF - Physica C: Superconductivity and its Applications
IS - 3-4
ER -