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arXiv · 1307.3422

Low-temperature phase diagram of Fe1+yTe

Cevriye Koz·Sahana Rößler·Alexander A. Tsirlin·Steffen Wirth·Ulrich Schwarz
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Abstract

We used low-temperature synchrotron x-ray diffraction to investigate the structural phase transitions of Fe1+yTe in the vicinity of a tricitical point in the phase diagram. Detailed analysis of the powder diffraction patterns and temperature dependence of the peak-widths in Fe1+yTe showed that two-step structural and magnetic phase transitions occur within the compositional range 0.11 $\leq y \leq $ 0.13. The phase transitions are sluggish indicating a strong competition between the orthorhombic and the monoclinic phases. We combine high-resolution diffraction experiments with specific heat, resistivity, and magnetization measurements and present a revised temperature-composition phase diagram for Fe1+yTe.

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Cevriye Koz, Sahana Rößler, Alexander A. Tsirlin, Steffen Wirth, Ulrich Schwarz. 2013-07-12. Low-temperature phase diagram of Fe1+yTe. https://doi.org/10.1103/physrevb.88.094509

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