This talk shall examine anomalous insulating and metallic signatures of FeSb
2. In our electrical transport measurements, we observe clear signatures of a metallic surface state at low temperatures. This offers a promising setting to explore the effects of strongly correlated 2D physics. Furthermore, despite being a bulk electrical insulator, we detect quantum oscillations in the bulk magnetisation under high applied magnetic fields, similar to previous observations in the analogous materials SmB
6 and YbB
12. Importantly, unlike in those materials we also uncover a strong connection between the unconventional insulating quantum oscillations in FeSb
2 and features in the background magnetisation. Our results point strongly to a magnetic origin for the phenomenon of insulating quantum oscillations in unconventional insulators.
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