Extended Data Fig. 1: Basic characterizations of TaIrTe4 flakes.
From: Dual quantum spin Hall insulator by density-tuned correlations in TaIrTe4
a, Optical image displaying exfoliated TaIrTe4 flakes on a Si/SiO2 substrate. b, Atomic force microscopy (AFM) image of a TaIrTe4 flake. Inset exhibits the linecut profile, indicating a step thickness of approximately 0.8 nm. c, Raman spectrum of TaIrTe4 flakes ranging from monolayers (1L) to three layers (3L). With increasing layer numbers, the intensity ratio of A2 (@125.7 cm−1 for 1L)/A2 (@137.3 cm−1 for 1L) rises, and the A1 mode (@231.8 cm−1 for 1L) shifts toward lower wavenumbers. d, Cross-sectional scanning transmission electron microscopy (STEM) images of monolayer, bilayer, and trilayer flakes.