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arXiv · 0811.2154

Pressure and alloying effects on the metal to insulator transition in NiS{2-x}Se{x} studied by infrared spectroscopy

A. Perucchi·C. Marini·M. Valentini·P. Postorino·R. Sopracase·P. Dore·P. Hansmann·O. Jepsen·G. Sangiovanni·A. Toschi·K. Held·D. Topwal·D. D. Sarma·S. Lupi
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Abstract

The metal to insulator transition in the charge transfer NiS{2-x}Se{x} compound has been investigated through infrared reflectivity. Measurements performed by applying pressure to pure NiS2 (lattice contraction) and by Se-alloying (lattice expansion) reveal that in both cases an anomalous metallic state is obtained. We find that optical results are not compatible with the linear Se-alloying vs Pressure scaling relation previously established through transport, thus pointing out the substantially different microscopic origin of the two transitions.

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A. Perucchi, C. Marini, M. Valentini, P. Postorino, R. Sopracase, P. Dore, P. Hansmann, O. Jepsen, G. Sangiovanni, A. Toschi, K. Held, D. Topwal, D. D. Sarma, S. Lupi. 2009-07-22. Pressure and alloying effects on the metal to insulator transition in NiS{2-x}Se{x} studied by infrared spectroscopy. https://arxiv.org/abs/0811.2154

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