Open AccessTwo-Dimensional Quantum Hall Effect and Zero Energy State in Few-Layer ZrTe5
Author(s) -
Fangdong Tang,
Peipei Wang,
Mingquan He,
Masahiko Isobe,
Genda Gu,
Qiang Li,
Liyuan Zhang,
J. H. Smet
Publication year - 2021
Publication title -
nano letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.853
H-Index - 488
eISSN - 1530-6992
pISSN - 1530-6984
DOI - 10.1021/acs.nanolett.1c00958
Subject(s) - topological insulator , condensed matter physics , quantum hall effect , surface states , semimetal , band gap , state of matter , quantum spin hall effect , gapless playback , physics , dirac (video compression format) , topology (electrical circuits) , zero point energy , quantum mechanics , surface (topology) , electron , combinatorics , neutrino , geometry , mathematics
Topological matter plays a central role in today's condensed matter research. Zirconium pentatelluride (ZrTe 5 ) has attracted attention as a Dirac semimetal at the boundary of weak and strong topological insulators (TI). Few-layer ZrTe 5 is anticipated to exhibit the quantum spin Hall effect due to topological states inside the band gap, but sample degradation inflicted by ambient conditions and processing has so far hampered the fabrication of high quality devices. The quantum Hall effect (QHE), serving as the litmus test for 2D systems to be considered of high quality, has not been observed so far. Only a 3D variant on bulk was reported. Here, we succeeded in preserving the intrinsic properties of thin films lifting the carrier mobility to ∼3500 cm 2 V -1 s -1 , sufficient to observe the integer QHE and a bulk band gap related zero-energy state. The magneto-transport results offer evidence for the gapless topological states within this gap.