Next Quantum Material Seminar:
Thursday 13 February, 2pm
Manuel Núñez-Regueiro (Institut Néel)
“Magnetic field sorting of superconducting graphite particles with Tc > 400K“
To access this seminar:
Institut Néel, Building K 1st floor, Room K223 Remy Lemaire
Zoom link:
https://univ-grenoble-alpes-fr.zoom.us/j/99704311337?pwd=DifLYnRYXc4ML48joXWxo5Q3sGJjkP.1
Abstract:
It has been claimed that graphite hosts superconductivity at room temperature, although all efforts to isolate it have been vain. Here we report separation methods that use magnetic field gradients to sort the superconducting from normal grains out of industrial graphite powders. We have obtained a concentrate of above room temperature superconducting particles. Electrical resistance measurements on agglomerates of sorted grains of synthetic, natural and spectroscopically pure graphite all show transition temperatures up to Tc^{onset}~700 K with zero resistance up to ~500K. Magnetization measurements confirm these values through jumps at Tc in the zero field cooled curves, and by the occurrence of diamagnetic hysteretic cycles shrinking with temperature. Transmission electron microscope images yield a hint of the novel structure of these grains.
Next scheduled seminars are:
Thursday 13 March: Claire Marrache Kikuchi (IJCLab, Orsay) to be confirmed
To subscribe to seminar announcements:
https://listes.grenoble.cnrs.fr/sympa/subscribe/quantum_materials_seminar
The organizers:
Elsa Lhotel, elsa.lhotel@neel.cnrs.fr
Florence Levy-Bertrand, florence.levy-bertrand@neel.cnrs.fr
