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arXiv · 1903.12375

Effect of synthesis conditions on the electrical resistivity of TiSe$_2$

Jaime M. Moya·C. -L. Huang·Jesse Choe·Gelu Costin·Matthew S. Foster·E. Morosan
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Abstract

Dilute impurities and growth conditions can drastically affect the transport properties of TiSe$_2$, especially below the charge density wave transition. In this paper, we discuss the effects of cooling rate, annealing time and annealing temperature on the transport properties of TiSe$_2$: slow cooling of polycrystalline TiSe$_2$ post-synthesis drastically increases the low temperature resistivity, which is in contrast to the metallic behavior of single-crystalline TiSe$_2$ due to charge doping from the residual iodine transport agent. A logarithmic increase of resistivity upon cooling and negative magnetoresistance with a sharp cusp around zero field are observed for the first time for the polycrystalline TiSe$_2$ samples, pointing to weak-localization effects due to low dimensionality. Annealing at low temperatures has a similar, but less drastic effect. Furthermore, rapid quenching of the polycrystalline samples from high temperatures freezes in disorder, leading to a decrease in the low temperature resistivity.

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Jaime M. Moya, C. -L. Huang, Jesse Choe, Gelu Costin, Matthew S. Foster, E. Morosan. 2019-03-29. Effect of synthesis conditions on the electrical resistivity of TiSe$_2$. https://doi.org/10.1103/physrevmaterials.3.084005

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