Gate tunable quantum oscillations in air-stable and high mobility few-layer phosphorene heterostructures

Abstract

As the only non-carbon elemental layered allotrope, few-layer black\nphosphorus or phosphorene has emerged as a novel two-dimensional (2D)\nsemiconductor with both high bulk mobility and a band gap. Here we report\nfabrication and transport measurements of phosphorene-hexagonal BN (hBN)\nheterostructures with one-dimensional (1D) edge contacts. These transistors are\nstable in ambient conditions for >300 hours, and display ambipolar behavior, a\ngate-dependent metal-insulator transition, and mobility up to 4000 $cm^2$/Vs.\nAt low temperatures, we observe gate-tunable Shubnikov de Haas (SdH)\nmagneto-oscillations and Zeeman splitting in magnetic field with an estimated\ng-factor ~2. The cyclotron mass of few-layer phosphorene holes is determined to\nincrease from 0.25 to 0.31 $m_e$ as the Fermi level moves towards the valence\nband edge. Our results underscore the potential of few-layer phosphorene (FLP)\nas both a platform for novel 2D physics and an electronic material for\nsemiconductor applications.\n