Evidence of topologically non-trivial phase trough unusual Shubnikov–de Haas oscillations*

Topological features in bulk related phenomena are still an uncharted territory as opposed to edge and surface effects, making Shubnikov-de Haas (SdH) oscillations an interesting phenomenon to explore in topological systems. Here we investigate the bulk magneto-oscillations in connection with topological bands of 2D systems. We describe our systems by the BHZ model [1] and use a convenient trace formula [2] to describe the density of states of broadened Landau levels within a phenomenological Drude-like transport description. Our preliminary results show unusual beatings in the SdH oscillations for the topological regime, which are absent in the trivial regime. These can be traced back to the coexistence of both electron- and hole-like carriers, present in the “Mexican hat” band structures. This suggests SdH oscillations as a possible bulk probe for the non-trivial band topology of 2D systems.

[1] B. Andrei Bernevig, Taylor L. Hughes, Shou-Cheng Zhang, Science 314, 1757 (2006).
[2] S. I. Erlingsson, J. V. I. Costa, D. R. Cândido, and J. C. Egues, Analytical results for the SdH oscillations in Rashba-Dresselhaus 2DEGs, (Unpublished)