Fig. 3: Shear engineering and measurements of HShPs with varying twist angles.
From: Engineering shear polaritons in 2D twisted heterostructures
a Optical image of α-MoO3 flakes with similar thicknesses at varying twist angles on a single α-MoO3 flake. Near-field images of HShPs for different twist angles: θ = 2° (d1 = 133 nm) (b); θ = 17° (d1 = 128 nm) (c); θ = 30° (d1 = 130 nm) (d); θ = 46° (d1 = 134 nm) (e), all with d2 = 202 nm. I2: second harmonic near-field signal. The x axis is along the [100] direction of the bottom α-MoO3 layer. Red dashed lines indicate the fitting direction of line intensity profiles used to extract the momentum-specific Q factor. f–i Experimental, and j–m simulated Fourier spectra, corresponding to (b–e). n The shear factor (red data) and the Q factor (blue data) grow for increasing twist angles θ from 0° to 90° due to increasing asymmetry in the system, as shown by both experimental (hollow dots) and simulated (solid dots) results. The error bars represent the 95% confidence intervals.
