Electronic, Optical, and Magnetic Properties of Doped Triangular MoS₂ Quantum Dots: A Density Functional Theory Approach

Abstract

A theoretical investigation on electronic states in triangular MoS2 quantum dots of different sizes is performed within density functional theory first‐principles formalism. Herein, the associated interband optical response from real and imaginary parts of the dielectric function is calculated. The study considers both undoped and Al‐, Si‐, and P‐doped systems. Spin‐related magnetic properties are considered through the evaluation of total magnetic moment. It is revealed that small enough structures have a semiconductor character, but evolve to seemingly half‐metallic with increasing dot size. Nonzero magnetic response is attributed to edge effects. Magnetic behavior of doped systems deviates from the linear dependence of the total magnetic moment with size occurring in the undoped case, producing situations with higher total momentum values. It is found that increasing the doping density may have certain influence over total magnetic moment response of the structures, although edge dominance is kept all the way. Optical properties are not as sensitive to incident light polarization, but they actually do with regard to the particular spin orientation. Calculation for the refraction index in the triangular quantum dots shows values still below the accepted in the MoS2 monolayer case, although a correct trend of variation is reported in this sense.

Structure, Stability, and Electronic Properties of Hydrogenated Monolayer 2D Silicon Allotropes by First‐Principles Calculation

“…In addition, all of these monolayer 2D silicon allotropes have high gravimetric hydrogen contents and maybe have applications for chemical hydrogen storage or water‐enabled H 2 production. [ 54–57 ] We believe that the results of this work have a good reference value for the experimental synthesis of hydrogenated monolayer 2D silicon allotropes, and have reference significance for understanding the diversity and electronic properties of hydrogenated monolayer 2D silicon allotropes.…”

Improving the Strain Control Performance of MoS2 Monolayer to Develop Flexible Electronics

“…Due to the atomic thickness and mechanical flexibility of MoS 2 , strain engineering provides an ideal platform for tuning its intrinsic electronic [42,43] and optical properties. [44][45][46][47][48][49] The strain engineering in current elections is achieved by doping. The larger germanium atom provides compression strain to the silicon channel with much-enhanced hole carrier mobility, and similarly, the smaller carbon atom creates tension strain and is used to increase the electron carrier mobility of silicon.…”

Wannier excitons confined in hexagonal boron nitride triangular quantum dots

“…Optical, electronic and magnetic properties of TMD quantum dots are of special interest for quantum computing. Various recent works have focused on the study of these properties via different methods, namely tight-binding [16][17][18], density functional theory [3,19] and continuum models [20][21][22]. Phase transitions to the metallic phase are also especially relevant, allowing for different charge excitation and decay pathways [23].…”