TY - JOUR
T1 - I-V characteristics of the vortex state in Mg B2 thin films
AU - Yang, Huan
AU - Jia, Ying
AU - Shan, Lei
AU - Zhang, Yingzi
AU - Wen, Hai Hu
AU - Zhuang, Chenggang
AU - Liu, Zikui
AU - Li, Qi
AU - Cui, Yi
AU - Xi, Xiaoxing
PY - 2007/10/23
Y1 - 2007/10/23
N2 - The current-voltage (I-V) characteristics of various Mg B2 films have been studied at different magnetic fields parallel to the c axis. At fields μ0 H between 0 and 5 T, vortex liquid-glass transitions were found in the I-V isotherms. Consistently, the I-V curves measured at different temperatures show a scaling behavior in the framework of quasi-two-dimension (quasi-2D) vortex-glass theory. However, at μ0 H≥5 T, a finite dissipation was observed down to the lowest temperature here, T=1.7 K, and the I-V isotherms did not scale in terms of any known scaling law, of any dimensionality. We suggest that this may be caused by a mixture of σ band vortices and π band quasiparticles. Interestingly, the I-V curves at zero magnetic field can still be scaled according to the quasi-2D vortex-glass formalism, indicating an equivalent effect of self-field due to persistent current and applied magnetic field.
AB - The current-voltage (I-V) characteristics of various Mg B2 films have been studied at different magnetic fields parallel to the c axis. At fields μ0 H between 0 and 5 T, vortex liquid-glass transitions were found in the I-V isotherms. Consistently, the I-V curves measured at different temperatures show a scaling behavior in the framework of quasi-two-dimension (quasi-2D) vortex-glass theory. However, at μ0 H≥5 T, a finite dissipation was observed down to the lowest temperature here, T=1.7 K, and the I-V isotherms did not scale in terms of any known scaling law, of any dimensionality. We suggest that this may be caused by a mixture of σ band vortices and π band quasiparticles. Interestingly, the I-V curves at zero magnetic field can still be scaled according to the quasi-2D vortex-glass formalism, indicating an equivalent effect of self-field due to persistent current and applied magnetic field.
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U2 - 10.1103/PhysRevB.76.134513
DO - 10.1103/PhysRevB.76.134513
M3 - Article
AN - SCOPUS:35448930674
SN - 1098-0121
VL - 76
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 13
M1 - 134513
ER -