Fig. 4: Excitation power and polarization dependence of edge photocurrent.
From: Robust edge photocurrent response on layered type II Weyl semimetal WTe2
a Power dependence of the edge photocurrent responses with 1.96-eV pulse excitation. b, c Scanning photocurrent microscopies under horizontal- (b) and vertical-polarized (c) light excitation respectively. The light polarization is marked by the red arrows. d Polarization dependent photocurrent responses with light focused on the spot marked by a red circle in Figure b. e–h Scanning photocurrent microscopies with excitation photon energies of 1.96 eV (e), 0.89 eV (f), 0.31 eV (g) and 0.12 eV (h) respectively. All measurements were performed on the device shown in Fig. 2a. The scale bars are all 8 μm.
