The interface between a 2D system and a 3D topological insulator is drawing interest in view of potential applications related to the exploitation of the proximity effect. The expression “proximity effect” encloses a series of phenomena occurring at the interface between a trivial insulator and a topological insulator. When a heterostructure is indeed built the properties of both the trivial and the topological insulator can undergo stunning changes. [1,2]
Here, we report recent results on the morphology and growth mode of antimony deposited on the surface of a prototypical topological insulator such as Bi2Se3. Indeed, antimony few layers are predicted to show the behaviour of trivial semiconductor .
STM measurements performed at room temperature show the formation of flat islands of buckled antimonene in the β-phase, as observed for few-layer antimonene . Atomic resolution images of both the bismuth selenide substrate and the antimonene overlayer show a well ordered structure and a perfect match between the two lattices, opening the possibility to exploit the antimonene as the suitable system to investigate its predicted peculiar electronic band structure  in presence of the topological surface states of the Bi2Se3. 
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