Professor He Lin's research group from the School of Physics and Astronomy, along with collaborators, published their academic findings titled "Realization of fractional-layer transition metal dichalcogenides" in Nature Communications.

The abstract of the paper is as follows:

Layered van der Waals transition metal dichalcogenides (TMDCs), generally composed of three atomic X-M-X planes in each layer (M = transition metal, X = chalcogen), provide versatile platforms for exploring diverse quantum phenomena. In each MX₂ layer, the M-X bonds are predominantly covalent in nature and, as a result, the cleavage of TMDC crystals normally occurs between the layers. Here we report the controllable realization of fractional-layer WTe₂ via an in-situ scanning tunneling microscopy (STM) tip manipulation technique. By applying STM tip pulses, hundreds of the topmost Te atoms are removed to form a nanoscale monolayer Te pit in the 1 T′-WTe₂, thus realizing a 2/3-layer WTe₂ film. Such a configuration undergoes a spontaneous atomic reconstruction, yielding a unidirectional charge density redistribution with the wavevector and geometry quite distinct from that of pristine 1 T′-WTe₂. Our results expand the conventional understanding of the TMDCs and are expected to stimulate further research on the structure and properties of fractional-layer TMDCs.

The source of the paper:

Ya-Xin Zhao, Heng Jin, Zi-Yi Han, Xinlei Zhao, Ya-Ning Ren, Ruo-Han Zhang, Xiao-Feng Zhou, Wenhui Duan, Bing Huang, Yu Zhang, Lin He. Realization of fractional-layer transition metal dichalcogenides. Nat. Commun. 16, 3659 (2025). https://doi.org/10.1038/s41467-025-59007-7