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arXiv · 1802.02969

Negative longitudinal magnetoresistance in the density wave phase of Y$_2$Ir$_2$O$_7$

Abhishek Juyal·Amit Agarwal·Soumik Mukhopadhyay
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Abstract

The ground state of nanowires of single crystalline Pyrochlore Y$_2$Ir$_2$O$_7$ is a density wave. Application of a {\it transverse} magnetic field increases the threshold electric field for the collective de-pinning of the density wave state at low temperature, leading to colossal magnetoresistance for voltages around the de-pinning threshold. This is in striking contrast to the case where even a vanishingly small {\it longitudinal} magnetic field sharply reduces the de-pinning threshold voltage resulting in {\it negative} magnetoresistance. Ruling out several other possibilities we argue that this phenomenon is likely to be a consequence of the chiral anomaly in the gapped out Weyl semimetal phase in Y$_2$Ir$_2$O$_7$.

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Abhishek Juyal, Amit Agarwal, Soumik Mukhopadhyay. 2018-02-08. Negative longitudinal magnetoresistance in the density wave phase of Y$_2$Ir$_2$O$_7$. https://doi.org/10.1103/physrevlett.120.096801

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