Figure 4: DFT computational simulation.
From: Free-electron creation at the 60° twin boundary in Bi2Te3
Atomic structures of (a) the unit-cell of Bi2Te3 and (b) Bi2Te3 with a 60° twin boundary. The dotted black line indicates the 60° twin boundary. (c) The projected density of states (PDOS) of bulk Bi2Te3, (d) the grain region and (e) the boundary region (bottom panel). Four different atoms are chosen to plot the PDOS at the boundary region (as marked in b). Navy, orange, red and blue coloured circles correspond to Te (1), Te (2), Bi (1) and Bi (2) atoms, respectively. Three panels (c–e) are aligned to match the valence band maximum. The calculated band gap is indicated by the shaded area with the colour yellow.
