Modulating via External Electric Field an Electronic Band Gaps in 2D 1T-PdS₂ monolayer

Abstract

We have examined structural stability and electronics properties of 2D 1T-PdS2 monolayer within the Density Functional Theory (DFT). 1T-PdS2 monolayer has indirect narrow band gap of 1.16 eV along the wave vector path of Γ-M-K-Γ in first Brillouin zone. The positive phonon dispersion curves at gamma point confirmed the dynamic stability of the 1T-PdS2 monolayer. Under the external electric field E → effect, the diverting nature has seen in the electronic band gaps within the intensity span of -5.0 V/Å to +5.0 V/Å along ±Z-direction. Hence, we could modulate the band gaps of semiconductor by applying external electric field, which is helpful for band engineering application. In this way, the semiconductor 2D 1T-PdS2 monolayer is capable candidate for nanoelectronics devices.

Detailed investigations on stability and optoelectronic characteristics of the 1T-PdS2 monolayer

“…It is apparent from figure 3 that the 1T-PdS 2 monolayer is an indirect bandgap semiconductor with the valence band maximum (VBM) and conduction band minimum (CBM) lying along the Γ -point and between Γ -M points, respectively. The obtained value of bandgap, E PBE , is 1.173 eV, which is quite comparable with earlier reported values, i.e., 1.11 eV [27], 1.24eV [38,54], 0.99 eV [55], and 1.16eV [44]. We have also calculated the bandgap using GGA + SOC and GGA + U (U=3.69) methods [35].…”

“…Upon examination of figure 2(a), it is observed that all frequencies in the vicinity of Γ -point are positive, indicating the dynamical stability of the structure. However, there is some distinction in the frequency scale of present phonon dispersion spectra, as compared to the one given by Raval et al [44]. This difference may occur due to the different methodology employed for performing the calculations.…”