Mott Transition, Antiferromagnetism, and Unconventional Superconductivity in Layered Organic Superconductors

S. Lefebvre; P. Wzietek; S. Brown; C. Bourbonnais; D. Jérome; C. Mézière; M. Fourmigué; P. Batail

doi:10.1103/PhysRevLett.85.5420

Mott Transition, Antiferromagnetism, and Unconventional Superconductivity in Layered Organic Superconductors

S. Lefebvre, P. Wzietek, S. Brown, C. Bourbonnais, D. Jérome, C. Mézière, M. Fourmigué, and P. Batail

Phys. Rev. Lett. 85, 5420 – Published 18 December 2000

Abstract

The phase diagram of the organic superconductor $κ - (ET)_{2} Cu [N (CN)_{2}] Cl$ has been accurately measured from $^{1} H$ NMR and ac susceptibility techniques under helium gas pressure. The domains of stability of antiferromagnetic and superconducting orders in the pressure vs temperature plane have been determined. Both phases overlap through a first-order boundary that separates two regions of inhomogeneous phase coexistence. The boundary curve merges with the first-order line of the metal-insulator transition which ends with a critical point at higher temperature. The whole phase diagram features a pointlike region where metallic, insulating, antiferromagnetic, and non-s-wave superconducting phases all meet.

Received 12 May 2000

DOI:https://doi.org/10.1103/PhysRevLett.85.5420

Authors & Affiliations

S. Lefebvre^1,2, P. Wzietek¹, S. Brown³, C. Bourbonnais², D. Jérome¹, C. Mézière⁴, M. Fourmigué⁴, and P. Batail⁴

¹Laboratoire de Physique des Solides (CNRS, U.R.A.2), Université de Paris-sud, Bâtiment 510, 91405 Orsay, France
²CERPEMA, Département de Physique, Université de Sherbrooke, Sherbrooke, Québec, Canada J1K 2R1
³Department of Physics and Astronomy, University of California at Los Angeles, Los Angeles, California 90095-1569
⁴Institut des Matériaux de Nantes, 44072 Nantes, France