Article

The Superconducting Ferromagnet UCoGe

Hanoi Advanced School of Science and Technology, Hanoi University of Technology, 1 Dai Co Viet, Hanoi, Vietnam
Journal of Low Temperature Physics (Impact Factor: 1.18). 01/2010; 161(1):134-147. DOI: 10.1007/s10909-010-0188-1
Source: arXiv

ABSTRACT The correlated metal UCoGe is a weak itinerant ferromagnet with a Curie temperature T
C=3K and a superconductor with a transition temperature T
s=0.6K. We review its basic thermal, magnetic—onthe macro and microscopic scale—and transport properties, as well as the
response to high pressure. The data unambiguously show that superconductivity and ferromagnetism coexist below T
s=0.6K and are carried by the same 5f electrons. We present evidence that UCoGe is a p-wave superconductor and argue that superconductivity is mediated by critical ferromagnetic spin fluctuations.

KeywordsSuperconducting ferromagnet-
p-wave superconductor-Magneticquantum critical point-Critical spin fluctuations

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