Theory of Valley-Density Wave and Hidden Order in Iron-Pnictides

Jian Kang; Zlatko Tesanovic

doi:10.1103/physrevb.83.020505

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arXiv · 1011.2499

Theory of Valley-Density Wave and Hidden Order in Iron-Pnictides

Jian Kang·Zlatko Tesanovic

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Abstract

In the limit of perfect nesting, the physics of iron-pnictides is governed by the density wave formation at the zone-edge vector M. At high energies, various spin- (SDW), charge- (CDW), orbital/pocket- (PDW) density waves, and their linear combinations, all appear equally likely, unified within the unitary order parameter of U(4)XU(4) symmetry. Nesting imperfections and low-energy interactions reduce this symmetry to that of real materials. Nevertheless, the generic ground state preserves a distinct signature of its highly symmetric origins: a SDW along one axis of the iron lattice is predicted to coexist with a perpendicular PDW, accompanied by weak charge currents. This "hidden" order induces the structural transition in our theory, naturally insures T_s >= T_N, and leads to orbital ferromagnetism and other observable consequences.

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Jian Kang, Zlatko Tesanovic. 2011-02-01. Theory of Valley-Density Wave and Hidden Order in Iron-Pnictides. https://doi.org/10.1103/physrevb.83.020505

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