Origin of diverse nematic orders in Fe-based superconductors: 45$^\circ$ rotated nematicity in AFe$_2$As$_2$ (A=Cs, Rb)

Seiichiro Onari; Hiroshi Kontani

doi:10.1103/PhysRevB.100.020507

paper

Origin of diverse nematic orders in Fe-based superconductors: 45 $^{\circ}$ rotated nematicity in AFe $_{2}$ As $_{2}$ (A=Cs, Rb)

arXiv:1809.08017 · doi:10.1103/PhysRevB.100.020507

Abstract

The origin of diverse nematicity and their order parameters in Fe-based superconductors have been attracting increasing attention. Recently, a new type of nematic order has been discovered in heavily hole-doped ( $n_{d} = 5.5$ ) compound AFe $_{2}$ As $_{2}$ (A=Cs, Rb). The discovered nematicity has $B_{2 g}$ (= $d_{x y}$ ) symmetry, rotated by $4 5^{\circ}$ from the $B_{1 g}$ (= $d_{x^{2} - y^{2}}$ ) nematicity in usual compounds with $n_{d} \approx 6$ . We predict that the "nematic bond order", which is the symmetry-breaking of the correlated hopping, is responsible for the $B_{2 g}$ nematic order in AFe $_{2}$ As $_{2}$ . The Dirac pockets in AFe $_{2}$ As $_{2}$ is essential to stabilize the $B_{2 g}$ bond order. Both $B_{1 g}$ and $B_{2 g}$ nematicity in A $_{1 - x}$ Ba $_{x}$ Fe $_{2}$ As $_{2}$ are naturally induced by the Aslamazov-Larkin many-body process, which describes the spin-fluctuation-driven charge instability. The present study gives a great hint to control the nature of charge nematicity by modifying the orbital character and the topology of the Fermi surface.

10 pages, 11 figures

Origin of diverse nematic orders in Fe-based superconductors: 45 $^{\circ}$ rotated nematicity in AFe $_{2}$ As $_{2}$ (A=Cs, Rb)

Abstract

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Origin of diverse nematic orders in Fe-based superconductors: 45∘ rotated nematicity in AFe2​As2​ (A=Cs, Rb)

Abstract

References in corpus (13)

Cited by in corpus (25)

Origin of diverse nematic orders in Fe-based superconductors: 45 $^{\circ}$ rotated nematicity in AFe $_{2}$ As $_{2}$ (A=Cs, Rb)