Strain-sensitive optical properties of monolayer tungsten diselenide

Divergent Vibrational Property Induced by an Anomalous Layer Sequence in Two-Dimensional GaPS4

“…The quantum mechanical calculation is extensively applied to elucidate the experimental results by providing a theoretical basis without empirical elements. − Several studies have reported the various intrinsic physical properties of GaPS 4 , such as the electronic band structure, phonon dispersion, dynamics, Poisson’s ratio, and transition dipole moment using quantum mechanical calculations. − By employing the density functional theory (DFT) and density functional perturbation theory (DFPT) methods to different stacking-sequence GaPS 4 ’s, we can analyze the various physical properties (e.g., electronic structure and phonon vibrational origin) occurring at the atomic scale. − To investigate the stacking-sequence-induced distinct physical properties of GaPS 4 , we used two different models (AA and AB sequences, as shown in Figure d). Specifically, because the AA- and AB-sequence structures have similar atomic arrangements at the (2 0 1) plane, the previously reported high-angle annular dark-field results , can be explained well (Figure S4 in the Supporting Information).…”