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arXiv · 0911.3878

In-plane electronic anisotropy in underdoped Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ revealed by detwinning in a magnetic field

Jiun-Haw Chu·James G. Analytis·David Press·Kristiaan De Greve·Thaddeus D. Ladd·Yoshihisa Yamamoto·Ian R. Fisher
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Abstract

We present results of angle-dependent magnetoresistance measurements and direct optical images of underdoped Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ which reveal partial detwinning by action of a 14T magnetic field. Driven by a substantial magneto-elastic coupling, this result provides evidence for an electronic origin of the lattice distortion in underdoped iron pnictides. The observed anisotropy in these partially detwinned samples implies a substantial in-plane electronic anisotropy in the broken symmetry state, with a smaller resistivity along the antiferromagnetic ordering direction.

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Jiun-Haw Chu, James G. Analytis, David Press, Kristiaan De Greve, Thaddeus D. Ladd, Yoshihisa Yamamoto, Ian R. Fisher. 2009-11-19. In-plane electronic anisotropy in underdoped Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ revealed by detwinning in a magnetic field. https://doi.org/10.1103/physrevb.81.214502

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