Fig. 2: Photon energy- and polarization-dependent photocurrent.
From: Multi-parameter control of photodetection in van der Waals magnet CrSBr
a Photon energy-dependent photocurrent under 2-µW incident light polarized along the b axis (green) and a axis (violet) at 1.65 K, showing significant anisotropic photocurrent over a wide spectral range from 1.30 eV to 1.93 eV. Inset depicts the band structure of bilayer CrSBr from a first-principle calculation, showing a flat conduction band along the Γ-X direction corresponding to the a axis, and dispersive bands along the Γ-Y direction corresponding to the b axis. Red and blue dashed arrows indicate the interband transitions from VBM1 to CBM and VBM2 to CBM. b Linear dichroic ratio defined by Iph−b/Iph−a, showing a high degree of polarization-sensitive response and prominent peaks at interband transitions (indicated by the dashed arrows). c, d Spatial mappings of photocurrent signal measured from D1 with light polarization along the b axis (c) and a axis (d). e Polarization-angle dependence of the photocurrent with incident light of 1.376 eV plotted in polar coordinates, where angle 0° (90°) corresponding to the b axis (a axis) of CrSBr
