BEHAVIOUR OF ORIENTED POLYCRYSTALLINE YBaCuO SUPERCONDUCTING THIN FILMS IN A WEAK MAGNETIC FIELD

1990 ◽  
Vol 04 (15) ◽  
pp. 975-982
Author(s):  
H.H. WEN ◽  
X.W. CAO ◽  
J.Z. SHI ◽  
W.Z. SHI ◽  
W.G. YAO ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Thin Films ◽  
Critical Field ◽  
Weak Magnetic Field ◽  
Flow Resistance ◽  
Weak Links ◽  
Superconducting Thin Films ◽  
Flux Flow ◽  
Granular Superconductivity ◽  
Oriented Polycrystalline

We determined a few characteristics of granular superconductivity through magnetoresistance measurements made on oriented polycrystalline YBaCuO superconducting thin films, and found that, at 77.3 K, the critical field for breaking a major portion of the superconducting weak links between grains was about 80 G, while the average lower critical field of the grains was about 175 G. Detail analyses on flux flow resistance show that a maximum of the increasing of flux flow resistance induced by a unit field will exist at a specified temperature, which we think is related to the dependence of the pinning energy on the temperature.

Fabrication and characteristics of weak links between â- and ĉ-axis normal grains of Y1Ba2Cu3O7−x

1996 ◽  
Vol 11 (5) ◽  
pp. 1086-1093
Author(s):  
S. Mahajan ◽  
D. B. Buchholz ◽  
J. Lei ◽  
R. P. H. Chang ◽  
T. Hogan ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Thin Films ◽  
Critical Current ◽  
Weak Coupling ◽  
Boundary Plane ◽  
Weak Links ◽  
Ion Milling ◽  
Flux Flow ◽  
Grain Boundary Plane ◽  
Current Voltage

We have used pulsed organometallic beam epitaxy (POMBE) to simultaneously deposit â- and ĉ-axis oriented Y1Ba2Cu3O7−x (YBCO) thin films at arbitrary locations on LaAlO3(100) substrates. Using photolithography and ion milling, several types of â-ĉ weak links have been fabricated at the boundary between the two films. The current-voltage (I-V) characteristics show a flux flow type behavior. The resistive transitions are broad and the critical current density is low, indicating weak coupling across these boundaries. With magnetic field applied parallel to the grain boundary plane, nonhysteretic I-V curves are obtained and the critical current goes to zero at an applied magnetic field of ∼7500 G.

ANOMALOUS BEHAVIORS OF NON-RESONANT MICROWAVE ABSORPTIONS OF SUPERCONDUCTORS

2000 ◽  
Vol 14 (16) ◽  
pp. 1633-1650
Author(s):  
K. SUGAWARA ◽  
N. ARAI ◽  
A. KOUZUKI ◽  
S. ICHIMURA ◽  
H. NAOI ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Thin Films ◽  
Applied Magnetic Field ◽  
Microwave Power ◽  
Superconducting Thin Films ◽  
Modulation Amplitude ◽  
Directional Effect ◽  
System A ◽  
Powder Samples ◽  
Preliminary Study

The non-resonant microwave absorption (NRMA) measurements have been intensively performed for superconducting thin films of YBa 2 Cu 3 O y fabricated on MgO (100) substrates and powder samples of LaSrCuO systems. In order to complement the study, we also review the NRMA of BiSrCaCuO system. A particular attention has been paid to the following phenomena: (i) phases, (ii) effect of current, (iii) directional effect of applied magnetic field, (iv) hysteresis, (v) microwave power absorbed as a function of magnetic field, (vi) linewidth in the vicinity of T c , and (vii) modulation amplitude effect. A preliminary study on ( La 0.98 Dy 0.02)1.85 Sr 0.15 CuO 4 was also reported.

scholarly journals Microwave properties of Fe(Se,Te) thin films in a magnetic field: pinning and flux flow

2020 ◽  
Vol 1559 ◽  
pp. 012055 ◽  
Author(s):  
Nicola Pompeo ◽  
Andrea Alimenti ◽  
Kostiantyn Torokhtii ◽  
Giulia Sylva ◽  
Valeria Braccini ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Thin Films ◽  
Microwave Properties ◽  
Flux Flow

scholarly journals Preparation of Bi-based Superconducting Thin Films by RF Magnetron Sputtering under Magnetic Field

Shinku ◽  
2004 ◽  
Vol 47 (3) ◽  
pp. 194-196
Author(s):  
Naoki FUJIWARA ◽  
Takahiro ONISHI ◽  
Kouji KATSURAHARA ◽  
Satoru KISHIDA
Keyword(s):  
Magnetic Field ◽  
Thin Films ◽  
Magnetron Sputtering ◽  
Rf Magnetron Sputtering ◽  
Superconducting Thin Films

scholarly journals Tuning Nanoscale Friction by Applying Weak Magnetic Fields to Reorient Adsorbed Oxygen Molecules

2018 ◽  
Vol 4 (1) ◽  
pp. 1 ◽  
Author(s):  
Z. Fredricks ◽  
K. Stevens ◽  
S. Kenny ◽  
B. Acharya ◽  
J. Krim
Keyword(s):  
Magnetic Field ◽  
Thin Films ◽  
Weak Magnetic Field ◽  
Quartz Crystal ◽  
Sliding Friction ◽  
Model Systems ◽  
Theoretical Studies ◽  
Weak Magnetic Fields ◽  
Gold Substrates

Sliding friction levels of thin (1–2 monolayers) and thick (~10 monolayers) oxygen films adsorbed on nickel and gold at 47.5 K have been measured by means of a quartz crystal microbalance (QCM) technique. Friction levels for the thin (thick) films on nickel in the presence of a weak magnetic field were observed to be approximately 30% (50%) lower than those recorded in the absence of the external field. Friction levels for thin films on gold were meanwhile observed to be substantially increased in the presence of the field. Magnetically-induced structural reorientation (magnetostriction) and/or realignment of adlayer spins, which respectively reduce structural and magnetic interfacial corrugation and commensurability, appear likely mechanisms underlying the observed field-induced reductions in friction for the nickel samples. Eddy current formation in the gold substrates may account for the increased friction levels in this system. The work demonstrates the role of magnetic effects in model systems that are highly amenable to theoretical studies and modeling.

Sign in / Sign up

Export Citation Format

Share Document