Quantum Hall states in inverted HgTe quantum wells probed by transconductance fluctuations

S. Mantion (1, 2) , Colin Avogadri (1, 2) , Sergey S. Krishtopenko (1, 3) , S. Gebert (4, 5) , Sandra Ruffenach (1, 3) , Christophe Consejo (1, 6) , S. Morozov (7) , N. N. Mikhailov (8) , S. A. Dvoretskii (8) , Wojciech Knap (1, 3) , Sébastien Nanot (1, 2) , Frederic Teppe (1, 3) , Benoit Jouault (1, 2)

1 L2C - Laboratoire Charles Coulomb
2 TQNS
3 Spectroscopie Térahertz
4 IES - Institut d’Electronique et des Systèmes
5 TéHO - Térahertz, hyperfréquence et optique
6 Axe Physique Appliquées
7 Institute for Physics of Microstructures of the RAS
8 ISP - Rzhanov Institute of Semiconductor Physics

We investigated quantum Hall states in an inverted HgTe quantum well (QW) close to the critical thickness using transconductance fluctuation (TF) measurements. In the conduction band, several integer quantum Hall states were observed, corresponding to filling factors ν=1,2,3,4. For magnetic fields above 2 T, quantum Hall states ν=0 were observed in the normal gap. These observations agreed well with the previous studies of quantum Hall states on GaAs QWs and graphene. Interestingly, TFs corresponding to anomalous positive filling factor ν were clearly observed in the valence band. We attribute the emergence of those TFs to the localization and charging of the heavy holes located in the side maxima of the valence band.

Domaines: Science des matériaux [cond-mat.mtrl-sci]; Systèmes mésoscopiques et effet Hall quantique [cond-mat.mes-hall]; Optique / photonique

S. Mantion, Colin Avogadri, Sergey S. Krishtopenko, S. Gebert, Sandra Ruffenach, et al.. Quantum Hall states in inverted HgTe quantum wells probed by transconductance fluctuations. Physical Review B, 2020, 102 (7), pp.075302. ⟨10.1103/PhysRevB.102.075302⟩. ⟨hal-02919868⟩