Fig. 4: Intrinsic photocurrent response in BPV devices via time-resolved photocurrent (TRPC) technique.
From: Dual polarization-enabled ultrafast bulk photovoltaic response in van der Waals heterostructures
a Schematic illustration of the TRPC measurement. The Δt indicates the delay time between pump and probe beams. b TRPC measurements of WSe2/BP BPV devices, pure BP two-terminal PV devices, and MoS2/BP BPV devices with different BP thicknesses. The hollow circles are experimental data and the solid red lines show the fitting of the data. c Representative optical images in different structures showing the signal collection positions at red dots. The green and yellow dash lines indicate the position of BP and monolayer TMDs. All scale bars are 6 μm. d Comparison of the BP thickness (L) dependence of the intrinsic response time (τ) in WSe2/BP BPV devices (orange dots), pure BP two-terminal PV devices (black dots), and MoS2/BP BPV devices (light blue dots). The orange, gray and light blue areas serve as guides for different BP thickness dependence of the intrinsic response time. Error bars correspond to the standard deviation from multiple measurements.
