The magnetic flux penetration into thin type-II superconducting films with circular defects is investigated. The artificial circular defects ~diameter 540 mm) in an YBa2Cu3O72d thin film ~thickness '300 nm) were prepared by pulse-laser irradiation. The flux penetration into the zero-field-cooled superconducting film was visualized by means of the magneto-optic method. A stepwise increase of the...

Oxypnictide thin film growth by pulsed laser deposition (PLD) is one of many insufficiently resolved issues in the research of iron-based superconductors. Here we report on the successful realization of superconducting SmO1-xFxFeAs oxypnictide thin film growth by in-situ PLD on CaF2 (fluorite) substrates. CaF2 acts as fluorine supplier by diffusion and thus enables superconducting oxypnictide t...

Thin film growth of iron chalcogenides by pulsed laser deposition (PLD) is still a delicate issue in terms of simultaneous control of stoichiometry, texture, substrate/film interface properties, and superconducting properties. The high volatility of the constituents sharply limits optimal deposition temperatures to a narrow window and mainly challenges reproducibility for vacuum based methods. ...

It is well known that intrinsic stress plays an important role in the superconducting material properties of niobium (Nb) thin films and in the resulting electrical characteristics of superconducting-insulating-superconducting (SIS) junctions made from these films. The role of sputtering pressure, gun operating parameters and substrate fixturing on Nb film stress has been investigated by a numb...

We present very low temperature Scanning Tunneling Microscopy and Spectroscopy (STM/S) measurements of a W based amorphous thin film grown with focused-ionbeam. In particular, we address the superconducting properties close to the border, where the thickness of the superconducting film decreases, and the Au substrate emerges. When approaching the Au substrate, the superconducting tunneling cond...

Thin superconducting films form a unique platform for geometrically-confined, strongly-interacting electrons. They allow an inherent competition between disorder and superconductivity, which in turn enables the intriguing superconducting-to-insulator transition and believed to facilitate the comprehension of high-Tc superconductivity. Furthermore, understanding thin film superconductivity is te...

Superconducting thin films have the potential to improve the performance of particle accelerators. Before these thin films can be implemented, a systematic study on structureproperty correlations is necessary. Here, we present the characterization of niobium thin films deposited onto both ceramic and metallic substrates. In particular, the film microstructure and superconducting properties are ...

SQUIDs are the most sensitive devices in detecting the magnetic flux. The devices have been used to detect small magnetic field, current, voltage, inductance and magnetic susceptibility etc. In this work, we reported studies and applications of high-Tc YBa2Cu3Oy SQUIDs. Two main techniques of depositing YBCO thin films are described; the characteristic of thin film and high-Tc SQUID are address...