Polarized photocurrent response in black phosphorus field-effect transistors

Nanoscale. 2014 Aug 7;6(15):8978-83. doi: 10.1039/c4nr02164a.


We investigate electrical transport and optoelectronic properties of field effect transistors (FETs) made from few-layer black phosphorus (BP) crystals down to a few nanometers. In particular, we explore the anisotropic nature and photocurrent generation mechanisms in BP FETs through spatial-, polarization-, gate-, and bias-dependent photocurrent measurements. Our results reveal that the photocurrent signals at BP-electrode junctions are mainly attributed to the photovoltaic effect in the off-state and photothermoelectric effect in the on-state, and their anisotropic feature primarily results from the directional-dependent absorption of BP crystals.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.