Aharon Kapitulnik , Stanford University

Jeudi 23 Avril 2015 14h
Aharon Kapitulnik , Stanford University
Amphi Holweck, Esc C, 1ème etage

Duality and an emerging Hall insulator phase and duality near the magnetic-field tuned superconductor-insulator transition

We combine measurements of the longitudinal and Hall resistivities of disordered two dimensional amorphous films to study the magnetic-field tuned superconductor to insulator transition (SIT) in the zero-temperature limit. We distinguish two different regimes for this transition. For weak disorder, intervening "metallic phases” with electron-hole symmetry character emerge above fields that are much smaller than the critical field. For strong disorder, a true superconductor to insulator transition is found, which is characterized by strongly inhomogeneous state. We find that in this regime the transition exhibits signatures of self-duality, and separates the superconducting state from a “Hall-insulator” phase. A higher characteristic magnetic field at which the Hall resistance is T independent marks a crossover to a Fermi-insulator, at which point the Hall resistance reaches the “canonical value” = H/nec. We also highlight a profound analogy between the magnetic-field tuned SIT and quantum-Hall liquid to insulator transitions.


Haut de page



À lire aussi...

Edwin Kermarrec, McMaster University

Jeudi 18 Décembre 2014, 10h30Amphi Boreau, Esc C, 2ème etage Exotic magnetism on the frustrated FCC lattice of 4d and 5d double perovskites Edwin (...) 

> Lire la suite...

Matthieu Delbecq, Center for Emergent Matter Science RIKEN

Jeudi 26 Novembre 2015 14h Amphi Holweck, Esc C, 1ème etage Multiple spin qubits in semiconductor quantum dots subject to nuclear spin bath (...) 

> Lire la suite...