Electrical and optoelectronic properties of few-layer black phosphorus field-effect transistors are investigated through spatial-, polarization-, gate-, and bias-dependent photocurrent measurements.

We investigate the photocurrent generation mechanisms at a vertical p–n heterojunction between black phosphorus (BP) and molybdenum disulfide (MoS ₂ ) flakes through polarization-, wavelength-, and gate-dependent scanning photocurrent measurements.