"Pressure effects on magnetically driven electronic nematic states in iron pnictide superconductors"

Jiangping Hu: Chandan Setty, and Steve Kivelson ; Phys. Rev. B, 03/26/12.

Additional Authors: Chandan Setty, and Steve Kivelson

Abstract:

In a magnetically driven electronic nematic state, an externally applied uniaxial strain rounds the nematic transition and increases the magnetic transition temperature. We study both effects in a simple classical model of the iron pnictides expressed in terms of local SO(N) spins (with N=3) which we solve to leading order in 1/N. The magnetic transition temperature is shown to increase linearly in response to an external strain while a sharp crossover, which is a remnant of the nematic transition, can only be identified for extremely small strain. We show that these results can reasonably account for recent neutron experimental data in BaFe2As2 by C. Dhital et al.