相关论文: Electron scattering dependence of dendritic magnet…
Magneto-opitcal studies of a c-oriented epitaxial MgB2 film show that below 10 K the global penetration of vortices is dominated by complex dendritic structures abruptly entering the film. We suggest that the observed behavior is due to a…
Magneto-opitcal studies of a c-oriented epitaxial MgB2 film with critical current density 10^7 A/cm^2 demonstrate a breakdown of the critical state at temperatures below 10 K [cond-mat/0104113]. Instead of conventional uniform and gradual…
Magneto-optical imaging reveals that in superconducting films of MgB2 a transport current creates avalanche-like flux dynamics where highly branching dendritic penetration patterns are formed. The instability is triggered when the current…
By doing magnetization measurements during magnetic field sweeps on thin films of the new superconductor $MgB_2$, it is found that in a low temperature and low field region small flux jumps are taking place. This effect strongly suppresses…
Using magneto-optical imaging the phenomenon of dendritic flux penetration in superconducting films was studied. Flux dendrites were abruptly formed in a 300 nm thick film of MgB2 by applying a perpendicular magnetic field. Detailed…
In this paper we present normal state magnetoresistivity data of magnesium diboride epitaxial thin films with different levels of disorder, measured at 42K in magnetic fields up to 45 Tesla. Disorder was introduced in a controlled way…
Magnetic relaxation and critical current density have been measured on a $MgB_2$ thin film in a wide region of temperature with the magnetic field up to 8 T. The irreversibility line has also been determined. It is found that the relaxation…
We have performed a comparative study of two thin films of magnesium diboride (MgB2) grown by different techniques. The critical current density at different temperatures and magnetic fields was evaluated from magnetisation curves, the…
The effects of neutron irradiation on normal state and superconducting properties of epitaxial magnesium diboride thin films are studied up to fluences of 1020 cm-2. All the properties of the films change systematically upon irradiation.…
Magneto-optical imaging was used to study a zero-field-cooled MgB2 film at 9.6K where in a slowly increasing field the flux penetrates by abrupt formation of large dendritic structures. Simultaneously, a gradual flux penetration takes…
We investigate the influence of carbon-ion irradiation on the superconducting critical properties of MgB$_2$ thin films. MgB$_2$ films of two thicknesses viz. 400 nm (MB400nm) and 800 nm (MB800nm) were irradiated by 350 keV C ions having a…
This paper presents a brief review on the reported anisotropic properties of MgB2, in the superconducting state (e.g. upper critical field Hc2, field penetration depth, coherence length, energy gap) as well as in the normal state (e.g.,…
A series of MgB$_2$ thin films systematically disordered by neutron irradiation have been studied by Scanning Tunneling Spectroscopy. The c-axis orientation of the films allowed a reliable determination of local density of state of the…
We investigate electron transport and phase-breaking processes in thin titanium nitride (TiN) films of epitaxial quality. Previous studies show that a minute surface magnetic disorder significantly reduces the critical temperature…
High-quality epitaxial MgB2 thin films prepared by pulsed laser deposition with Tc = 39 K offer the opportunity to study the anisotropy and robustness of the superconducting state in magnetic fields. We measure the in-plane electrical…
The inelastic magnetic scattering of neutrons from thin superconducting films irradiated with microwave radiations, is analyzed. This process is due to the interaction of the magnetic field generated by the neutron, with the oscillating…
Thin films of the recently discovered magnesium diboride (MgB2) intermetalic superconducting compound have been grown using a magnetron sputtering deposition technique followed by in-situ annealing at 830 C. High quality films were obtained…
Angle dependent torque measurements have been carried out on the organic superconductor, kappa-(ET)2Cu(NCS)2 at extremely low temperatures (25 - 300 mK). Magneto-thermal instabilities are observed in the form of abrupt magnetization (flux)…
Upper critical fields of four MgB2 thin films were measured up to 28 Tesla at Grenoble High Magnetic Field Laboratory. The films were grown by Pulsed Laser Deposition and showed critical temperatures ranging between 29.5 and 38.8 K and…
We report magnetoresistance (MR) measurements on MgB2 and the corresponding full account from ab-initio calculations; we suggest that this combination can be a useful tool to probe electron- phonon coupling. We obtain good quantitative…