Silicene in its freestanding atomic structure is low-buckled, although planar form has also been predicted [1]. The planar silicene has recently been synthesized on Au(111) films grown on Si(111) substrate in the process of surface segregation [2]. Its electronic structure is different than in the case of the freestanding form. Nevertheless the linear bands do exist, although they exhibit more complex dispersion patterns in Brillouin zone. The presence of such exotic Dirac fermions originates from the complex Si-Au structure with twisted layers [3]. The morphology of the substrate plays a substantial role in the synthesis of the planar silicene.

This work has been supported by the National Science Centre under Grant No. DEC-2018/29/B/ST5/01572.

References:

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2) A. Stępniak-Dybala, P. Dyniec, M. Kopciuszyński, R. Zdyb, M. Jałochowski, M. Krawiec, Adv. Funct. Mater. 29, 1906053 (2019).

3) T. Jaroch, M. Krawiec, R. Zdyb, 2D Mater. 8, 035038 (2021).