Fig. 5: Mid-infrared electroluminescence in the BP–MoS2 heterojunction diode.
From: Black phosphorus-based van der Waals heterostructures for mid-infrared light-emission applications
a, b Schematic band diagram of the BP–MoS2 heterojunction diode for Vds < 0, Vg = 0 (a) and Vds > 0, Vg > 0 (b). c EL at 80 K, Ids = 8.05 μA (orange line) and at 300 K, Ids = 8.50 μA (blue line). d EL intensity as a function of source–drain current Ids when Vds > 0. The yellow solid line serves as a guide line. e Polarization-resolved EL emission at 80 K and Ids = 8.05 μA. The solid line is the fitting curve obtained using the equation I = (Imax − Imin) cos2θ + Imin. Here, θ is the polarization angle referenced to the armchair axis of BP, and Imax and Imin are the EL intensities along the armchair- and zigzag-directions, respectively
