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arXiv · 1005.1330

Dimensional Tuning of the Magnetic-Structural Transition in A(Fe$_{1-x}$Co$_x$)$_2$As$_2$ (A=Sr,Ba)

Jack Gillett·Sitikantha D. Das·Paul Syers·Alison K. T. Ming·Jose I. Espeso·Chiara M. Petrone·Suchitra E. Sebastian
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Abstract

A phase diagram of superconducting Sr(Fe$_{1-x}$Co$_x$)$_2$As$_2$ as a function of doping (x) is determined by a series of thermodynamic and transport measurements on single crystals. On comparison with a similar phase diagram for Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ (Co-doped Ba122), we find that the increased dimensionality of Co-doped Sr122 results in a single first-order-like transition where the magnetic and structural transitions coincide, unlike the case of Co-doped Ba122 that exhibits split quasicontinuous magnetic and structural transitions. We relate this dimensionally-tuned splitting in the magnetic and structural transitions to the relative size of superconducting temperatures in these materials.

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Jack Gillett, Sitikantha D. Das, Paul Syers, Alison K. T. Ming, Jose I. Espeso, Chiara M. Petrone, Suchitra E. Sebastian. 2010-05-08. Dimensional Tuning of the Magnetic-Structural Transition in A(Fe$_{1-x}$Co$_x$)$_2$As$_2$ (A=Sr,Ba). https://arxiv.org/abs/1005.1330

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