Electron-hole asymmetry and quantum critical point in hole-doped BaFe 2 As 2
2008; Institute of Physics; Volume: 84; Issue: 6 Linguagem: Inglês
10.1209/0295-5075/84/67015
ISSN1286-4854
AutoresGang Xu, Haijun Zhang, Xi Dai, Zhong Fang,
Tópico(s)Physics of Superconductivity and Magnetism
ResumoWe show, from first-principles calculations, that the hole-doped side of Fe-As–based compounds is different from its electron-doped counterparts. The electron side is characterized as an itinerant metal with Fermi surface nesting, and SDW-to-NM quantum critical point (QCP) is realized by doping. For the hole-doped side, on the other hand, orbital-selective magnetic ordering develops together with checkboard anti-ferromagnetic (AF) ordering without lattice distortion. A unique SDW-to-AF QCP is achieved, and the J2=J1/2 criterion (in the approximate J1&J2 model) is satisfied at a hole-doping level of about x=0.7. The observed superconductivity is located in the vicinity of QCP for both sides.
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