Chiral spin texture induced weak localization and topological Hall effect in a fully compensated ferrimagnetic metal V$_2$NbAl

Interference-induced quantum corrections to electronic transport have been an interesting area to achieve a deeper insight into the physics of localization/antilocalization.

Here, we report quantum interference phenomena in a three-dimensional (3D) system, namely the full Heusler alloy V$_2$NbAl, attributed to the presence of chiral spin texture at low temperatures. We observe a crossover from weak localization (WL) to weak antilocalization (WAL) and a large topological Hall effect (THE), which are explained based on the local symmetry breaking arising out of intrinsic disorder. The extracted phase coherence length ($l_{\phi}\simeq$ 23 nm at 2 K) turns out to be much larger than the mean free path further confirming the quantum diffusive nature of transport.

The present study comprehensively explores the interplay between non-trivial spin texture and new exotic quantum transport arising out of antisite disorder present in V$_2$NbAl. {\it Ab-initio} calculations confirm a metallic state with fully compensated ferrimagnetism (FCF) for the experimentally confirmed B2-disordered structure of V$_2$NbAl. Overall, this work provides valuable insights into the origin of unconventional quantum transport and the associated underlying physics in a 3D system featuring chiral spin texture.