Fig. 1: Design of the misaligned unipolar barrier photodetector.
a Energy band profiles of black arsenic phosphorus (b-AsP), molybdenum disulfide (MoS2), black phosphorus (bP) before equilibrium. b, c Energy band diagrams for misaligned unipolar barrier photodetector under forward and reverse bias, respectively. Under forward bias (reverse bias), the photogenerated carriers from absorbing layer bP (b-AsP) with a cutoff wavelength of λ1 (λ2) can be collected to form a photocurrent. Ec, Ev, and Ef are the conduction band, valence band, and Fermi level, respectively. d Schematic of the device, composed of vertically stacked b-AsP/MoS2/bP heterostructure. e, f Schematic diagrams for misaligned unipolar barrier photodetector under forward and reverse bias, respectively. AC and ZZ axes correspond to the armchair and zigzag direction of crystal structure. The device is sensitive to the polarization of incident light at polarization angle P1 (along the AC direction of bP) under forward bias, and at polarization angle P2 (along the AC direction of b-AsP) at the reverse bias.
