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arXiv · 2303.13999

Near coincidence of metal-insulator transition and quantum critical fluctuations: Electronic ground state and magnetic order in Fe$_{1-x}$Co$_{x}$Si

J. Grefe·P. Herre·Y. Hilgers·F. Labbus·N. Lüer-Epping·N. Radomski·M. A. C. de Melo·F. J. Litterst·D. Menzel·S. Süllow
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Abstract

We present a detailed study of the electronic and magnetic ground state properties of Fe$_{1-x}$Co$_{x}$Si using a combination of macroscopic and microscopic experimental techniques. From these experiments we quantitatively characterize the metal-insulator transition and magnetic/non-magnetic quantum phase transition occurring at low doping levels in Fe$_{1-x}$Co$_{x}$Si. From our study, we find a surprising closeness of the critical composition of the metal-insulator transition at $x_{\mathrm{MIT}} = 0.014$ and the quantum phase transition at $x_{\mathrm{LRO}} \sim 0.024-0.031$. It suggests that these effects are cooperative and depend on each other.

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J. Grefe, P. Herre, Y. Hilgers, F. Labbus, N. Lüer-Epping, N. Radomski, M. A. C. de Melo, F. J. Litterst, D. Menzel, S. Süllow. 2023-03-24. Near coincidence of metal-insulator transition and quantum critical fluctuations: Electronic ground state and magnetic order in Fe$_{1-x}$Co$_{x}$Si. https://arxiv.org/abs/2303.13999

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