We demonstrate that a field effect transistor (FET) made of few layer black phosphorus (BP) encapsulated in hexagonal boron nitride (h-BN) in vacuum, exhibts the room temperature hole mobility of 5200 cm2/Vs being limited just by the phonon scattering. At cryogenic tempeature the FET mobility increases up to 45,000 cm2/Vs, which is eight times higher compared with the mobility obtained in earlier reports. The unprecedentedly clean h-BN/BP/h-BN heterostructure exhibits Shubnikov-de Haas oscillations and quantum Hall effect with Landau level (LL) filling factors down to v=2 in conventional laboratory magnetic fields. Moreover, carrier density independent effective mass m=0.26 m_0 is measured, and Lande g-factor g=2.47 is reported. Furthermore, an indication for a distinct hole transport behavior with up and down spin orientation is found.
@article{arxiv.1510.06518,
title = {Quantum Hall Effect in Ultrahigh Mobility Two-dimensional Hole Gas of Black Phosphorus},
author = {Gen Long and Denis Maryenko and Junying Shen and Shuigang Xu and Jianqiang Hou and Zefei Wu and Wing Ki Wong and Tianyi Han and Jiangxiazi Lin and Yuan Cai and Rolf Lortz and Ning Wang},
journal= {arXiv preprint arXiv:1510.06518},
year = {2016}
}