Signatures of Chiral Anomaly in the Magnetoresistance of a Quasi-3-Dimensional Electron Gas at the Interface of LaVO${}_3$ and KTaO${}_3$

Abstract

In a Dirac semimetal charges flow between two Weyl nodes when electric and magnetic fields (B||E) are parallel to each other manifesting interesting physical properties such as negative longitudinal magnetoresistance, planar Hall effect and anisotropic magnetoresistance. We observe a co-existence of weak antilocalization with large negative longitudinal magnetoresistance and an unusual Hall resistance with (B||E) configuration, at the conducting interface of LaVO${}_3$ and KTaO${}_3$. The depth of the conducting channel at the interface is estimated to be around 30 nm by using spectroscopy techniques of photoluminescence and time-correlated single-photon counting. Both planar Hall effect and anisotropic magnetoresistance exhibit oscillatory behaviour as a function of the angle between E and B. A very similar temperature dependence of negative longitudinal magnetoresistance, planar Hall effect and anisotropic magnetoresistance suggest a strong correlation among them.

10 pages, 3 figures