Extended Data Fig. 7: Stacking order of device 6 at different fabrication stages.

a, Optical image of the graphite flake (left) and the corresponding Raman map with a step size of 0.8 μm × 0.8 μm (right). Scale bar, 10 μm. b, Optical image of the graphite flake encapsulated by hBN (left) and the corresponding Raman map with a step size of 0.7 μm × 0.7 μm (right). Scale bar, 10 μm. c, Optical image of the finished Hall bar (left) and the corresponding Raman map with a step size of 0.5 μm × 0.5 μm (right). Scale bar, 4 μm. The colour coding of the Raman maps in a–c indicates the ratio of the integrated area of the low-frequency component (ranging around 2,635–2,665 cm⁻¹) to that of the high-frequency component (ranging around 2,665–2,695 cm⁻¹) of the graphite Raman 2D band. The coloured dots in a–c mark the positions where the Raman spectra shown in e were taken. d, Optical image showing that the Hall bar device is made from the ABC stacked region. Scale bar, 10 μm. e, Typical 2D Raman peaks of RG (dots a, c and d) and of graphite of mixed ABA and ABC stacking (dot b). Laser excitation wavelength, 633 nm.