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arXiv · 1510.07486

Solitonic spin-liquid state due to the violation of the Lifshitz condition in Fe$_{1+y}$Te

Ph. Materne·C. Koz·U. K. Rößler·M. Doerr·T. Goltz·H. H. Klauss·U. Schwarz·S. Wirth·S. Rößler
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Abstract

A combination of phenomenological analysis and Mössbauer spectroscopy experiments on the tetragonal Fe$_{1+y}$Te system indicates that the magnetic ordering transition in compounds with higher Fe-excess, $y\ge$ 0.11, is unconventional. Experimentally, a liquid-like magnetic precursor with quasi-static spin-order is found from significantly broadened Mössbauer spectra at temperatures above the antiferromagnetic transition. The incommensurate spin-density wave (SDW) order in Fe$_{1+y}$Te is described by a magnetic free energy that violates the weak Lifshitz condition in the Landau theory of second-order transitions. The presence of multiple Lifshitz invariants provides the mechanism to create multidimensional, twisted, and modulated solitonic phases.

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Ph. Materne, C. Koz, U. K. Rößler, M. Doerr, T. Goltz, H. H. Klauss, U. Schwarz, S. Wirth, S. Rößler. 2015-10-26. Solitonic spin-liquid state due to the violation of the Lifshitz condition in Fe$_{1+y}$Te. https://doi.org/10.1103/physrevlett.115.177203

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