Spin-resolved band structure of heterojunction Bi-bilayer/3D topological insulator in the quantum dimension regime in annealed Bi2Te2.4Se0.6

Abstract

Two- and three-dimensional topological insulators are the key materials for the future nanoelectronic and spintronic devices and quantum computers. By means of angle- and spin-resolved photoemission spectroscopy we study the electronic and spin structure of the Bi-bilayer/3D topological insulator in quantum tunneling regime formed under the short annealing of Bi2Te2.4Se0.6. Owing to the temperature-induced restructuring of the topological insulator’s surface quintuple layers, the hole-like spin-split Bi-bilayer bands and the parabolic electronic-like state are observed instead of the Dirac cone. Scanning Tunneling Microscopy and X-ray Photoemission Spectroscopy measurements reveal the appearance of the Bi2 terraces at the surface under the annealing. The experimental results are supported by density functional theory calculations, predicting the spin-polarized Bi-bilayer bands interacting with the quintuple-layers-derived states. Such an easily formed heterostructure promises exciting applications in spin transport devices and low-energy electronics.

Impact of stoichiometry and disorder on the electronic structure of the PbBi2Te4−xSex topological insulator

“…The most studied of them are compounds with tetradymite-like structure in which each atomic layer consists of only one sort of atoms. However, it is possible to obtain the disordered alloys with similar structure but with statistical distribution of different types of atoms [10][11][12][13][14][15][16]. In practice, the variation of the composition of multicomponent compounds allows for tuning the Fermi level to energy gap in materials where it is located in the bulk band, owing to the residual bulk charge induced by crystal defects [10][11][12][14][15][16][17][18].…”

Regularities of the quantum spin Hall phase formation in three-dimensional tetradymite-like topological insulator thin films

“…3). As can be seen from Table I At the same time, intriguing topological properties can be expected in the case of thin films of recently studied 3D TI Bi 2 Te 2.4 Se 0.6 [60,61]. A distinct feature of this compound is the existence of two possible types of disordering [59,62] [ Fig.…”

Topological electronic structure and Rashba effect in Bi thin layers: theoretical predictions and experiments

“…Using such an approach problems connected with epitaxial growth can be solved in a simple way. Subsequently, the atomic and electronic structures of Bi(1 1 1) films grown on Bi 2 Te 3 , Bi 2 Se 3 , Bi 2 Te 2 Se and Bi 2 Te 2.4 Se 0.6 [91,141,[143][144][145][146][147][148] have been determined by means of several techniques, namely ARPES, and compared to first-principles calculations. Some of the results have been reviewed in [37].…”