Multilayer phosphorene quantum dots in an electric field: Energy levels and optical absorption

Abstract

Triangular and hexagonal multilayer phosphorene quantum dots with armchair and zigzag terminations are investigated with the orthogonal tight-binding model. The effect of increasing the number of layers is revealed. The obtained results show that in a small size multilayer quantum dot the edge states are as sensitive to the out-of-plane external electric fields as the edge states in a single layer dot to the in-plane external electric fields. The investigated optical absorption cross sections show that armchair phosphorene quantum dots have a regular behavior which should be useful for infrared detectors. In particular, it was found that in hexagonal armchair phosphorene dots absorption peaks can be increased, decreased, or totally removed from the low-energy region depending on the orientation of the applied electric field. The effect of spurious doping can suppress the transitions < 0.4 eV, while effect of the finite temperature is almost negligible.

Interaction of hydrated metals with chemically modified hexagonal boron nitride quantum dots: wastewater treatment and water splitting

“…However, the hBN quantum dots have been hardly investigated, especially in comparison with the graphene and other 2D material based quantum dots (for instance Refs. [61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76][77] etc.). Nevertheless, some studies on structural stability, magnetic, optical and adsorption properties can be found in the literature.…”

Tunable electro-optical properties of doped chiral graphene nanoribbons

“…For instance, y-directed field (parallel to the zigzag edge) will provide an oscillating effect on the low energy molecular orbitals at the zigzag edge. While the filed applied in x-direction (perpendicular to the zigzag edge) will increase the small E g between the edge states in GNR4-W3-L4 and decrease the wide band gap between the surface extended states in doped GNR4-W3-L4-OBO similar to its effect on hexagonal flakes with zigzag edges reported in [56]. Similarly, the y-field in the latter case decreases the band gap.…”

Wigner molecules in phosphorene quantum dots

“…Phosphorene quantum dots [36][37][38][39][40][41][42][43] in the form of small flakes have been extensively studied, in particular from the point of view of optical properties. In this work we consider a clean electrostatic confinement that keeps the confined electrons off the edge of the flake.…”