Strain Modulated Electronic, Mechanical, and Optical Properties of the Monolayer PdS₂, PdSe₂, and PtSe₂ for Tunable Devices

Abstract

We study the electronic, mechanical and optical properties of the monolayer PdS 2 , PdSe 2 and PtSe 2 under mechanical strains of various magnitudes and directions. It is found that the band structures of these materials are more sensitive to biaxial strains. Moreover, the Young's modulus of all three materials are calculated in the a and b directions. Simulation results show the Young's modulus of monolayer PdS 2 , PdSe 2 and PtSe 2 are 116.4 GPa, 58.5 GPa and 115.9 GPa in the a direction and 166.5 GPa, 123.6 GPa and 117.7 GPa in the b direction. We analyze the peak shift of the real (߳ ଵ ) and imaginary (߳ ଶ ) parts of the complex dielectric constants for these three materials. We found that the peak of the complex dielectric constant red-shifts towards lower energy and ߳ ଵ (0) monotonously increase with the compressive and tensile strains increase. Among these three materials, PdS 2 exhibits excellent electronic and optical tunability under tensile strains, for example the peak wavelength of the imaginary dielectric constant can be adjusted from 2 eV to 1 eV when the strain varies from 0% to 10%, leading to approximately 5% red-shift in wavelength per 1% mechanical tensile strain. The results indicate that these monolayer materials will have potential applications in tunable nanoelectromechanical devices.

Electronic and optical properties of Janus ZrSSe by density functional theory

“…37 However, compared with other transition metal dichalcogenide monolayers, we found that in the presence of tensile strain, while the band gap of the Janus ZrSSe increased slightly, the band gap of the transition metal dichalcogenide monolayers, such as PdS 2 , PdSe 2 , and PtSe 2 , was signicantly reduced. 38,39 In both cases of strain engineering and external electric eld, from Fig. 6 and 7, we see that the change of band gap is due to the change of the conduction band.…”

Light Confinement Effect Induced Highly Sensitive, Self‐Driven Near‐Infrared Photodetector and Image Sensor Based on Multilayer PdSe2/Pyramid Si Heterojunction

“…The periodic boundary conditions were applied in horizontal direction to simulate an infinite area, and the perfectly matched layer (PML) boundary conditions were set on the top/bottom sides. The dielectric constants of Si and PdSe 2 were chosen from previous work …”

A Review of Experimental and Computational Advances in Thermal Boundary Conductance and Nanoscale Thermal Transport across Solid Interfaces

“…Mechanical strain can be used to modify the optical, thermal and electrical properties of materials . High pressures can be used to increase the strength of bonds and stiffen the interface, which offers a novel pathway to control interfacial chemistry and therefore interfacial heat transfer .…”

“…Mechanical strain can be used to modify the optical, thermal and electrical properties of materials. [181][182][183][184][185][186] High pressures can be used to increase the strength of bonds and stiffen the interface, which offers a novel pathway to control interfacial chemistry and therefore interfacial heat transfer. [187] In general, the application of hydrostatic pressure causes the spring constant that holds the atoms in their equilibrium position to increase.…”