Temperature-dependent magnetospectroscopy of HgTe quantum wells

A. V. Ikonnikov , Sergey S. Krishtopenko (1) , Oleksiy Drachenko , Michel Goiran , Maksim Zholudev (1) , V. V. Platonov , Yu. B. Kudasov , A. S. Korshunov , D. A. Maslov , I. V. Makarov , O. M. Surdin , A. V. Philippov , M. Marcinkiewicz (1) , Sandra Ruffenach (1) , Frederic Teppe (1) , Wojciech Knap (1) , N. N. Mikhailov , S. A. Dvoretsky , V. I. Gavrilenko

1 L2C - Laboratoire Charles Coulomb

We report on magnetospectroscopy of HgTe quantum wells in magnetic fields up to 45 T in a temperature range from 4.2 up to 185 K. We observe intra- and inter-band transitions from zero-mode Landau levels, which split from the bottom conduction and upper valence sub-bands and merge under the applied magnetic field. To describe experimental results, realistic temperature-dependent calculations of Landau levels have been performed. We show that although our samples are topological insulators at low temperatures only, the signature of such a phase persists in optical transitions at high temperatures and high magnetic fields. Our results demonstrate that temperature-dependent magnetospectroscopy is a powerful tool to discriminate trivial and topological insulator phases in HgTe quantum wells.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

A. V. Ikonnikov, Sergey S. Krishtopenko, Oleksiy Drachenko, Michel Goiran, Maksim Zholudev, et al.. Temperature-dependent magnetospectroscopy of HgTe quantum wells. Physical Review B, 2016, 94 (15), pp.155421. ⟨10.1103/PhysRevB.94.155421⟩. ⟨hal-01397638⟩