Fig. 2: Steady-state photoresponse of photodetectors.
From: Waveguide-integrated twisted bilayer graphene photodetectors
a False color scanning electron microscopic (SEM) image of a waveguide-integrated tBLG photodetector. The white dashed box denotes the region of tBLG. Scale bar: 2 μm. b Photocurrent as a function of bias voltage Vb for 4.1° tBLG, AB-stacking BLG, and SLG photodetectors, respectively. c Photocurrent as a function of wavelength for 4.1° tBLG, AB-stacking BLG, and SLG photodetectors at a Vb of 0.5 V, respectively. d Power dependence of the photoresponsivity at a Vb of 0.5 V for 4.1° tBLG, AB-stacking BLG, and SLG photodetectors, respectively. e Statistical histogram of photoresponsivity from 16 devices. Red, green, and blue colors denote 4.1° tBLG, AB-stacking BLG, and SLG photodetectors, respectively. f Comparisons of the photoresponsivity versus the graphene length with previously reported waveguide-integrated graphene photodetectors using different optimization strategies, including pristine planar photodiodes35,36,44,45,50,53, vertical photosensitive heterostructures48,54, gate engineering46,47, and plasmonic enhancement9,12,51/photonic structure design13,49,52.
