Concept

Hélium liquide

Publications associées (104)

Test results of a 10 kA current lead using Ag/Au stabilized Bi-2223 tapes

In the frame of the European Fusion Technology Programme, the Forschungszentrum Karlsruhe and the CRPP Villigen are developing a 60 kA current lead for the ITER Toroidal Field Coils using High Temperature Superconductors. In part 2 of the task, two 10 kA H ...

2000

Superfluid and normal-fluid densities in the high-T-c superconductors

Giorgio Margaritondo, László Forró, Helmuth Berger

In clean metallic superconductors, 100% of the mobile carriers participate ill the condensate, so that the London penetration depth (which measures the electromagnetic screening by the superconductor) indicates charge densities comparable to those inferred ...

2000

ab-plane optical properties of Ni-doped Bi2Sr2CaCu2O8+delta

Giorgio Margaritondo, Helmuth Berger

The ab-plane optical reflectance of single crystal of Bi2Sr2Ca(Cu1-xNix)(2)O8+d, for x = 0.0215, has been measured from 80 to 40 000 cm(-l) (10 meV-5 eV) and at temperatures between 20 and 300 K. Through Ni substitution, the optical conductivity shows a br ...

1999

Carbon-13 spectral editing in solid-state NMR using heteronuclear scalar couplings

David Lyndon Emsley

The feasibility of spectral editing techniques making use of heteronuclear scalar couplings in solid-state CPMAS NMR is demonstrated for powder samples exhibiting line widths of several tens of hertz such as ordinary amino acids. These simple and robust ex ...

AMER CHEMICAL SOC1998

The QUELL experiment as a validation tool for the numerical code Gandalf

Luca Bottura

One goal of the QUELL experiment is the validation of numerical codes for the simulation of thermo-hydraulic transients in Cable-in-Conduit Conductors with Central Channel (C-5). The validation of Gandalf has focused on 17 quench propagation runs. In gener ...

1998

Effects of segregation on the optical properties of (In,Ga)As/GaAs quantum wells grown by MBE under various conditions

Nicolas Grandjean

Thermally detected optical absorption measurements have been performed at liquid helium temperature in order to study the effects of In segregation on the optical properties of InxGa1-xAs/GaAs quantum wells grown by molecular-beam epitaxy under various gro ...

1997

Cathodoluminescence And Transmission Electron-Microscopy Study Of Island Formation On Inas/Inp Qw Structures During Growth Interruptions

Jean-François Carlin, Alok Rudra

A study on the effect of growth interruptions on InAs/InP strained quantum wells (QW) by cathodoluminescence (CL) at helium temperature and transmission electron microscopy (TEM) is reported. The samples are grown by chemical beam epitaxy (CBE) with and wi ...

Iop1994

Comparison of the Lateral Carrier Transport between a Gaas Single-Quantum-Well and the Algaas Barrier During Cathodoluminescence Excitation

Franz-Karl Reinhart, Jean-Daniel Ganière

In a recent paper we measured the lateral hole diffusion in a GaAs/AlGaAs single quantum well (SQW) by a novel method. At helium temperature, we estimate a lateral hole diffusion length in the QW of 1.5 mum. However, the assumption that diffusion takes pla ...

1994

INDIUM SEGREGATION AND MISORIENTATION EFFECTS ON THE OPTICAL-PROPERTIES OF MBE GROWN IN0.35GA0.65AS/GAAS QUANTUM-WELLS

Nicolas Grandjean

Photoluminescence (PL), reflectivity and thermally-detected optical absorption (TDOA) experiments have been carried out, at liquid helium temperatures, On In0.35Ga0.65As/GaAs quantum wells (QWs) with different thicknesses of 4, 6, 8 and 10 monolayers (MLs) ...

1993

Low‐Temperature EBIC Study of Zn‐Diffused GaAs p‐n Junctions

Franz-Karl Reinhart, Jean-Daniel Ganière

To study the effect of damage induced during the Zn diffusion on the properties of the material, p-n junctions, obtained by zinc diffusion, are investigated by electron beam induced current (EBIC) at different temperatures. At helium temperature, the EBIC ...

1992

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