YBCO superconducting films were prepared by Electron Beam Coevaporation method.All the YBCO films were annealed at 760°C in humidity range of 2.3-?9.5.Microstructure of the YBCO thin films was analyzed by means o...YBCO superconducting films were prepared by Electron Beam Coevaporation method.All the YBCO films were annealed at 760°C in humidity range of 2.3-?9.5.Microstructure of the YBCO thin films was analyzed by means of X-ray diffraction(XRD) and scanning electron microscopy(SEM).Superconducting properties of the YBCO films were measured by electromagnetic induction method.XRD results showed that c-axis-oriented grains existed in the YBCO films.Morphologies of the YBCO films showed that all the films had a smooth and crack-free surface.YBCO films prepared at 7.3% humidity condition showed Jc value of 4.6 MA cm-2 at 77 K in self-field.展开更多
We firstly described a simulation model to investigate the influence of grain boundary(GB)on the vortex transport properties in YBCO film.It is found that the size of inhomogeneous area caused by GB as well as the ave...We firstly described a simulation model to investigate the influence of grain boundary(GB)on the vortex transport properties in YBCO film.It is found that the size of inhomogeneous area caused by GB as well as the average velocity in transverse and longitudinal directions shows an angular dependence when the angle between the GB and the sample edge varies.We have also studied the impact of magnetic field intensity on dynamic behavior of vortex lattice and found that a lower vortex density makes it difficult for the vortex lattice to transfer from pinning state to flow state.As the magnetic field is decreased beyond a critical value,sharp jumps and strong fluctuations were observed in the I-V curve.Finally,we conducted measurements on a thin film YBa2Cu3O7 with an individual artificial grain boundary to support the simulation process.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.10921062 and 10502051)
文摘YBCO superconducting films were prepared by Electron Beam Coevaporation method.All the YBCO films were annealed at 760°C in humidity range of 2.3-?9.5.Microstructure of the YBCO thin films was analyzed by means of X-ray diffraction(XRD) and scanning electron microscopy(SEM).Superconducting properties of the YBCO films were measured by electromagnetic induction method.XRD results showed that c-axis-oriented grains existed in the YBCO films.Morphologies of the YBCO films showed that all the films had a smooth and crack-free surface.YBCO films prepared at 7.3% humidity condition showed Jc value of 4.6 MA cm-2 at 77 K in self-field.
基金supported by the National Basic Research Program of China("973"Project)(Grant Nos.2011CBA00107 and 2014CB339804)the National Natural Science Foundation of China(Grant Nos.61371036,11234006 and 11227904)+1 种基金the Natural Science Foundation of Jiangsu(Grant No.BK2012013)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘We firstly described a simulation model to investigate the influence of grain boundary(GB)on the vortex transport properties in YBCO film.It is found that the size of inhomogeneous area caused by GB as well as the average velocity in transverse and longitudinal directions shows an angular dependence when the angle between the GB and the sample edge varies.We have also studied the impact of magnetic field intensity on dynamic behavior of vortex lattice and found that a lower vortex density makes it difficult for the vortex lattice to transfer from pinning state to flow state.As the magnetic field is decreased beyond a critical value,sharp jumps and strong fluctuations were observed in the I-V curve.Finally,we conducted measurements on a thin film YBa2Cu3O7 with an individual artificial grain boundary to support the simulation process.