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arXiv · 1612.07341

Effect of biaxial strain on the phase transitions of Ca(Fe1-xCox)2As2

A. E. Böhmer·A. Sapkota·A. Kreyssig·S. L. Bud'ko·G. Drachuck·S. M. Saunders·A. I. Goldman·P. C. Canfield
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Abstract

We study the effect of applied strain as a physical control parameter for the phase transitions of Ca(Fe1-xCox)2As2 using resistivity, magnetization, x-ray diffraction and 57Fe Mössbauer spectroscopy. Biaxial strain, namely compression of the basal plane of the tetragonal unit cell, is created through firm bonding of samples to a rigid substrate, via differential thermal expansion. This strain is shown to induce a magneto-structural phase transition in originally paramagnetic samples; and superconductivity in previously non-superconducting ones. The magneto-structural transition is gradual as a consequence of using strain instead of pressure or stress as a tuning parameter.

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A. E. Böhmer, A. Sapkota, A. Kreyssig, S. L. Bud'ko, G. Drachuck, S. M. Saunders, A. I. Goldman, P. C. Canfield. 2016-12-21. Effect of biaxial strain on the phase transitions of Ca(Fe1-xCox)2As2. https://doi.org/10.1103/physrevlett.118.107002

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