In insulators, the longitudinal resistivity becomes infinitely large at zero temperature. For classic insulators, the Hall conductivity becomes zero at the same time. However, there are special systems, such as two-dimensional quantum Hall isolators, in which a more complex scenario is observed at high magnetic fields. Here, we report experimental evidence for a quasi-quantized Hall insulator in the quantum limit of the three-dimensional semimetal SrSi2. Our measurements reveal a magnetic field-range, in which the longitudinal resistivity diverges with decreasing temperature, while the Hall conductivity approaches a quasi-quantized value that is given only by the conductance quantum and the Fermi wave vector in the field-direction. The quasi-quantized Hall insulator appears in a magnetic-field induced insulating ground state of three-dimensional materials and is deeply rooted in quantum Hall physics.
@article{arxiv.2106.11329,
title = {Three-dimensional quasi-quantized Hall insulator phase in SrSi2},
author = {Kaustuv Manna and Nitesh Kumar and Sumanta Chattopadhyay and Jonathan Noky and Mengyu Yao and Joonbum Park and Tobias Förster and Marc Uhlarz and Tirthankar Chakraborty and B. Valentin Schwarze and Jacob Hornung and Vladimir N. Strocov and Horst Borrmann and Chandra Shekhar and Yan Sun and Jochen Wosnitza and Claudia Felser and Johannes Gooth},
journal= {arXiv preprint arXiv:2106.11329},
year = {2022}
}
Comments
29 pages including SI, 3 main figures and 6 SI figures