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arXiv · 1506.04823

Correlation of Crystal Quality and Extreme Magnetoresistance of WTe$_2$

Mazhar N. Ali·Leslie Schoop·Jun Xiong·Steven Flynn·Quinn Gibson·Max Hirschberger·N. P. Ong·R. J. Cava
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Abstract

High quality single crystals of WTe$_2$ were grown using a Te flux followed by a cleaning step involving self-vapor transport. The method is reproducible and yields consistently higher quality single crystals than are typically obtained via halide assisted vapor transport methods. Magnetoresistance (MR)values at 9 Tesla and 2 Kelvin as high as 1.75 million \%, nearly an order of magnitude higher than previously reported for this material, were obtained on crystals with residual resistivity ratio (RRR) of approximately 1250. The MR follows a near B$^2$ law (B = 1.95(1)) and, assuming a semiclassical model, the average carrier mobility for the highest quality crystal was found to be ~167,000 cm$^2$/Vs at 2 K. A correlation of RRR, MR ratio and average carrier mobility ($\mu_{avg}$) is found with the cooling rate during the flux growth.

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Mazhar N. Ali, Leslie Schoop, Jun Xiong, Steven Flynn, Quinn Gibson, Max Hirschberger, N. P. Ong, R. J. Cava. 2015-06-16. Correlation of Crystal Quality and Extreme Magnetoresistance of WTe$_2$. https://arxiv.org/abs/1506.04823

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