44 research outputs found
Coated conductor technology for the beamscreen chamber of future high energy circular colliders
The surface resistance of state-of-the-art REBa2Cu3O7−x coated conductors has been measured
at 8 GHz versus temperature and magnetic field. We show that the surface resistance of
REBa2Cu3O7−x strongly depends on the microstructure of the material. We have compared our
results to those determined by the rigid fluxon model. The model gives a very good qualitative
description of our data, opening the door to unravel the effect of material microstructure and
vortex interactions on the surface resistance of high temperature superconductors. Moreover, it
provides a powerful tool to design the best coated conductor architecture that minimizes the infield
surface resistance. We have found that the surface resistance of REBa2Cu3O7−x at 50 K and
up to 9 T is lower than that of copper. This fact poses coated conductors as strong candidate to
substitute copper as a beamscreen coating in CERN’s future circular collider. To this end we
have also analyzed the secondary electron yield (SEY) of REBa2Cu3O7−x and found a
compatible coating made of sputtered Ti and amorphous carbon that decreases the SEY close to
unity, a mandatory requirement for the beamscreen chamber of a circular collider in order to
prevent the electron-cloud phenomenon.Peer reviewe