Topological magnetotransport properties of micron-scale CoSi Hall bars fabricated by focused ion beam milling

Abstract

Topological quantum materials have sparked a thriving area of research aiming at the investigation of novel and exotic topological properties. In this work we focus on the chiral semimetal CoSi, which is predicted to behave a nearly-ideal topological conductor. In particular, we make use of focused ion beam milling to fabricate micron-scale multiterminal Hall bar devices of CoSi and analyze their magnetotransport properties, including transverse and longitudinal magnetoresistance and Hall effect, as a function of temperature and external magnetic field. Our results reveal the complex interplay between magnetotrasport and topological aspects in CoSi at the micron scale.