Superconducting Parity Effect at The Anderson limit


What is the minimum size for a nanocrystal to be superconducting ? In 1959, P.W. Anderson suggested that superconductivity could exists only when the energy interval between electronic levels is smaller than the superconducting energy scale, i.e. the superconducting gap, which corresponds to the binding energy of the Cooper pairs responsible for superconductivity. Until now, this remained a conjecture. However, using a Scanning Tunneling Microscope (STM) to study superconducting Lead (Pb) nanocrystals grown on the 2D electron gaz at the surface of Indium Arsenide, LPEM researchers have observed that Cooper pairing disappears when this level spacing became larger than this superconducting energy scale, demonstrating the validity of the Anderson criterion. This experiment establishes a new method for investigating nanocrystals in the regime of strong quantum confinement with promising perspectives for the study of electronic orders in the chemical limit, i.e. when the electronic spectrum of a solid becomes discrete.

Ref.
• Superconducting parity effect across the Anderson limit”
S. Vlaic, S. Pons, T. Zhang, A. Assouline, A. Zimmers, C. David, G. Rodary, J.C. Girard, D. Roditchev, H. Aubin. Nature Comm. 10.1038/NCOMMS14549

Contact : herve.aubin (arobase) espci.fr
Site Web : http://qtg.lpem.espci.fr

Haut de page



À lire aussi...

Engineering Bicolor Emission in 2D Core/Crown CdSe/CdSe1-xTex Nanoplatelet Heterostructures Using Band-offset Tuning

Marion Dufour1, Violette Steinmetz2, Eva Izquierdo1, Thomas Pons1, Nicolas Lequeux1, Emmanuel Lhuillier2, Laurent Legrand2, Maria Chamarro2, (...) 

> Lire la suite...

Détection d’ondes gravitationelles par VIRGO

Le 14 août 2017 à 10h30 UTC, le détecteur d’ondes gravitationnelles franco-italien Virgo (http://www.virgo-gw.eu/ ), conjointement avec les deux (...) 

> Lire la suite...