Critical current density measurement of thin films by AC susceptibility based on the penetration parameter h

2012 ◽  
Vol 477 ◽  
pp. 6-14 ◽  
Author(s):  
Xiao-Fen Li ◽  
Jean-Claude Grivel ◽  
Asger B. Abrahamsen ◽  
Niels H. Andersen
2006 ◽  
Vol 20 (15) ◽  
pp. 923-929
Author(s):  
C. SBÂRCIOG ◽  
T. R. REDAC ◽  
I. GR. DEAC

Ca -doped (x = 0.00, 0.07 and 0.20) epitaxial Y 1-x Ca x Ba 2 Cu 3 O 7-δ thin films were prepared on SrTiO 3 (100) by PLD technique. The superconducting transition temperature is found to decrease with increasing Ca content. The AC-susceptibility data were used to determine the intergranular critical current density, when varying the field amplitude H AC . The temperature dependence of critical current density was determined from the imaginary part of the complex susceptibility, χ′′(T), using Xing's relation. The results were analyzed in terms of superconductor-insulator-superconductor (SIS) and superconductor-normal-superconductor (SNS) type models.


Author(s):  
P. Lu ◽  
W. Huang ◽  
C.S. Chern ◽  
Y.Q. Li ◽  
J. Zhao ◽  
...  

The YBa2Cu3O7-x thin films formed by metalorganic chemical vapor deposition(MOCVD) have been reported to have excellent superconducting properties including a sharp zero resistance transition temperature (Tc) of 89 K and a high critical current density of 2.3x106 A/cm2 or higher. The origin of the high critical current in the thin film compared to bulk materials is attributed to its structural properties such as orientation, grain boundaries and defects on the scale of the coherent length. In this report, we present microstructural aspects of the thin films deposited on the (100) LaAlO3 substrate, which process the highest critical current density.Details of the thin film growth process have been reported elsewhere. The thin films were examined in both planar and cross-section view by electron microscopy. TEM sample preparation was carried out using conventional grinding, dimpling and ion milling techniques. Special care was taken to avoid exposure of the thin films to water during the preparation processes.


2021 ◽  
Vol 22 ◽  
pp. 14-19
Author(s):  
Soon-Gil Jung ◽  
Duong Pham ◽  
Jung Min Lee ◽  
Yoonseok Han ◽  
Won Nam Kang ◽  
...  

1989 ◽  
Vol 169 ◽  
Author(s):  
X.K. Wang ◽  
D.X. Li ◽  
S.N. Song ◽  
J.Q. Zheng ◽  
R.P.H. Chang ◽  
...  

AbstractEpitaxial thin films of YBaCuO were prepared by multilayer deposition from Y, Cu, and BaF2 sources with: (1) the a‐axis perpendicular to (100)SrTiO3; (2) the c‐axis perpendicular to (100)SrTiO3; and (3) the [110] axis perpendicular to (110)SrTiO3. XRD patterns as well as SEM and HREM images confirm that the films are highly oriented, essentially epitaxial. Both the a‐axis oriented and the c‐axis oriented films exhibit zero resistance at 91K. The [110] oriented film shows the sharpest transiton with a transition width of IK and zero resistance at 85K. The zero field critical current density, Jc, determined magnetically, is in excess of 107A/cm2 at 4.4K and 1.04 x 106A/cm2 at 77K for the c‐axis oriented film; for the a‐axis oriented film we obtained 6.7 x 106A/cm2 at 4.4K and 1.2 x 105A/cm2 at 77K. The orientation dependence of the critical current density in the basal plane of the a‐axis oriented film was studied. The largest Jc's occur along the in‐plane <100> axes of the substrate.


1999 ◽  
Vol 13 (13) ◽  
pp. 1645-1654 ◽  
Author(s):  
I. GR. DEAC ◽  
E. BURZO ◽  
A. V. POP ◽  
V. POP ◽  
R. TETEAN ◽  
...  

The intergranular properties of ( Y 1-x-y Zr x Ca y) Ba 2 Cu 3 O 7-δ ceramics were studies by using temperature-dependent ac susceptibility measurements at zero dc magnetic field. The intergranular critical current density was determined from ac susceptibility data by varying the field amplitude H ac . From the imaginary part of the complex susceptibility, χ″(T), we have determined the temperature dependence of the critical current density by using the Bean's model. The ac field dependencies of the intergrain χ″-peak temperatures T p are linear and agree with Müller critical state model. The results were analyzed in terms of superconductor-insulator-superconductor (SIS)-and superconductor-normal-superconductor (SNS)-type models for granular superconductors.


1995 ◽  
Vol 250 (1-2) ◽  
pp. 55-58 ◽  
Author(s):  
R.L. Wang ◽  
H.C. Li ◽  
B. Yin ◽  
J.W. Li ◽  
X.S. Ron ◽  
...  

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