We report the effects of hydrostatic pressure on the temperature-induced phase transitions in Fe1.08Te in the pressure range 0-3 GPa using synchrotron powder x-ray diffraction (XRD). The results reveal a plethora of phase transitions. At ambient pressure, Fe1.08Te undergoes simultaneous first-order structural symmetry-breaking and magnetic phase transitions, namely from the paramagnetic tetragonal (P4/nmm) to the antiferromagnetic monoclinic (P2_1/m) phase. We show that, at a pressure of 1.33 GPa, the low temperature structure adopts an orthorhombic symmetry. More importantly, for pressures of 2.29 GPa and higher, a symmetry-conserving tetragonal-tetragonal phase transition has been identified from a change in the c/a ratio of the lattice parameters. The succession of different pressure and temperature-induced structural and magnetic phases indicates the presence of strong magneto-elastic coupling effects in this material.
@article{arxiv.1209.1255,
title = {Pressure-induced phase transitions and high-pressure tetragonal phase of Fe1.08Te},
author = {C. Koz and S. Rößler and A. A. Tsirlin and D. Kasinathan and C. Börrnert and M. Hanfland and H. Rosner and S. Wirth and U. Schwarz},
journal= {arXiv preprint arXiv:1209.1255},
year = {2012}
}