%0 Journal Article %T Terahertz imaging of Landau levels in HgTe-based topological insulators %+ Institut d’Electronique et des Systèmes (IES) %+ Térahertz, hyperfréquence et optique (TéHO) %+ Laboratoire Charles Coulomb (L2C) %A Kadykov, Aleksandr M. %A Torres, Jeremie %A Krishtopenko, Sergey S. %A Consejo, Christophe %A Ruffenach, Sandra %A Marcinkiewicz, Michal %A But, Dmytro %A Knap, Wojciech %A Morozov, Sergey V. %A Gavrilenko, Vladimir I. %A Mikhailov, Nikolai N. %A Dvoretsky, Sergey A. %A Teppe, Frederic %< avec comité de lecture %Z L2C:16-118 %@ 0003-6951 %J Applied Physics Letters %I American Institute of Physics %V 108 %N 26 %P 262102 %8 2016-06-27 %D 2016 %R 10.1063/1.4955018 %Z Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Journal articles %X We report on sub-terahertz photoconductivity under the magnetic field of a two dimensional topologicalinsulator based on HgTe quantum wells. We perform a detailed visualization of Landau levelsby means of photoconductivity measured at different gate voltages. This technique allows oneto determine a critical magnetic field, corresponding to topological phase transition from invertedto normal band structure, even in almost gapless samples. The comparison with realistic calculationsof Landau levels reveals a smaller role of bulk inversion asymmetry in HgTe quantum wellsthan it was assumed previously. %G English %L hal-01358769 %U https://hal.science/hal-01358769 %~ CNRS %~ IES %~ L2C %~ MIPS %~ UNIV-MONTPELLIER %~ UM-2015-2021