Events

Next Quantum Materials/ LANEF seminar:

Thursday, February 13th 2025 at 2:00 pm

Manuel Núñez-Regueiro (Institut Néel)

“ Magnetic field sorting of superconducting graphite particles with Tc > 400K “

To access this seminar:

Institut Néel CNRS, Bâtiment K, Room Rémy Lemaire  (K223)

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.

The organizers:

Elsa Lhotel (elsa.lhotel@neel.cnrs.fr)
Florence Levy-Bertrand (florence.levy-bertrand@neel.cnrs.fr)