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In this paper, we investigate the electronic, optical, and thermoelectric properties of Ga2SSe monolayer by using density functional theory. Via analysis of the phonon spectrum and ab initio molecular dynamics simulations, Ga2SSe is confirmed to be stable at room temperature. Our calculations demonstrate that Ga2SSe exhibits indirect semiconductor characteristics and the spin–orbit coupling (SOC) effect has slightly reduced its band gap. Besides, the band gap of Ga2SSe depends tightly on the biaxial strain. When the SOC effect is included, small spin–orbit splitting energy of 90 meV has been found in the valence band. However, the spin–orbit splitting energy dramatically changes in the presence of biaxial strain. Ga2SSe exhibits high optical absorption intensity in the near-ultraviolet region, up to 8.444 × 104 cm−1, which is needed for applications in optoelectronic devices. By using the Boltzmann transport equations, the electronic transport coefficients of Ga2SSe are comprehensively investigated. Our calculations reveal that Ga2SSe exhibits a very low lattice thermal conductivity and high figure of merit ZT and we can enhance its ZT by temperature. Our findings provide further insight into the physical properties of Ga2SSe as well as point to prospects for its application in next-generation high-performance devices.

In this paper, we design and predict the structural, electronic, transport, and optical properties of two-dimensional Janus $\mathrm{GaIn}X\mathrm{O}$ ($X=\mathrm{S}$, Se, Te) monolayers by using first-principles calculations. The stability of all six possible configurations of $\mathrm{GaIn}X\mathrm{O}$ was examined through the analysis of their phonon spectra. It is found that, except for the OGaInTe monolayer, all the other configurations are dynamically stable. Further, the mechanical stability has been also investigated via calculations for the elastic constants. Depending on the stacking configuration, $\mathrm{GaIn}X\mathrm{O}$ can be either semiconductor (with a direct or indirect band gap) or metallic. Interestingly, the carrier mobilities of the investigated systems are found to be highly directional isotropic; however, the mobility of electrons is much higher than that of holes, suggesting that these monolayers can be potential materials for applications in nanoscale electronics. Finally, strong optical absorption in a wide light region extending from the infrared to the ultraviolet region is also predicted in the Janus $\mathrm{GaIn}X\mathrm{O}$ depending on its stacking configuration. The findings not only get insights into the fundamental properties of the Janus materials based on group III monochalcogenide monolayers but also suggest them as potential candidates for applications in the next-generation optoelectronic nanodevices.

In the present study, the effects of the strain engineering and electric field on electronic properties of the GaS monolayer are investigated by ab initio investigations. Our calculated results demonstrate that the GaS monolayer is a semi-conductor with a large indirect bandgap of 2.568 eV at the equilibrium. In the presence of a biaxial strain, the band structure of the GaS monolayer, especially the conduction band, changes significantly. However, while the effect of compressive strain on the energy gap of the GaS monolayer is quite weak, its energy gap depends strongly on the tensile strain. On the other hand, external electric fields can cause the semiconductor–metal transition in the monolayer. Being able to control electronic properties, especially the occurrence of the semiconductor–metal phase transition, makes the GaS monolayer a prospective material for nanoelectromechanical and nanospintronic applications.

In this work, we consider systematically the influence of uniaxial strain and external electric field E on electronic properties of a monolayer InSe using ab initio approach based on density functional theory. Our calculations indicate that the monolayer InSe has a medium indirect energy bandgap of 1.38 eV at equilibrium. The calculated results also demonstrate that we can adjust the bandgap of the monolayer InSe by strain engineering or electric field. The bandgap of the monolayer InSe changes dramatically when the uniaxial strain is applied. Especially, under the compressed uniaxial strain, an indirect–direct bandgap transition has been observed at certain elongations. Within the electric field magnitude E range from 0 to 5 V/nm, the calculated results show that the negative electric field changes the bandgap of the monolayer InSe up to 23% while the positive electric field effect on its bandgap is negligible.

Inspired by the successfully experimental synthesis of Janus structures recently, we systematically study the electronic, optical, and electronic transport properties of Janus monolayers In2 XY (X/Y = S, Se, Te with X ≠ Y) in the presence of a biaxial strain and electric field using density functional theory. Monolayers In2 XY are dynamically and thermally stable at room temperature. At equilibrium, both In2STe and In2SeTe are direct semiconductors while In2SSe exhibits an indirect semiconducting behavior. The strain significantly alters the electronic structure of In2 XY and their photocatalytic activity. Besides, the indirect–direct gap transitions can be found due to applied strain. The effect of the electric field on optical properties of In2 XY is negligible. Meanwhile, the optical absorbance intensity of the Janus In2 XY monolayers is remarkably increased by compressive strain. Also, In2 XY monolayers exhibit very low lattice thermal conductivities resulting in a high figure of merit ZT, which makes them potential candidates for room-temperature thermoelectric materials.

HIV-1 infects 39.5 million people worldwide, and cART is effective in preventing viral spread by reducing HIV-1 plasma viral loads to undetectable levels. However, viral reservoirs persist by mechanisms, including the inhibition of autophagy by HIV-1 proteins (i.e., Nef and Tat). HIV-1 reservoirs can be targeted by the ���shock and kill��� strategy, which utilizes latency-reversing agents (LRAs) to activate latent proviruses and immunotarget the virus-producing cells. Yet, limitations include reduced LRA permeability across anatomical barriers and immune hyper-activation. Ionizing radiation (IR) induces effective viral activation across anatomical barriers. Like other LRAs, IR may cause inflammation and modulate the secretion of extracellular vesicles (EVs). We and others have shown that cells may secrete cytokines and viral proteins in EVs and, therefore, LRAs may contribute to inflammatory EVs. In the present study, we mitigated the effects of IR-induced inflammatory EVs (i.e., TNF-��), through the use of mTOR inhibitors (mTORi; Rapamycin and INK128). Further, mTORi were found to enhance the selective killing of HIV-1-infected myeloid and T-cell reservoirs at the exclusion of uninfected cells, potentially via inhibition of viral transcription/translation and induction of autophagy. Collectively, the proposed regimen using cART, IR, and mTORi presents a novel approach allowing for the targeting of viral reservoirs, prevention of immune hyper-activation, and selectively killing latently infected HIV-1 cells.

We comprehensively study the electronic and optical properties of InTe monolayer in the presence of biaxial strain and electric field using density functional theory. Via analysis phonon spectrum, InTe monolayer is confirmed to be dynamically stable. InTe monolayer has an indirect semiconducting characteristic with a band gap of 1.25 eV at equilibrium and can be controlled by strain or electric field. The semiconductor–metal phase transition has been found in InTe monolayer at a large electric field of E = 5 V/nm. The optical attributes of InTe monolayer depend strongly on the polarization direction of the incident light. The optical absorption coefficient is activated in the infrared region and increases rapidly in the visible light region. While optical properties are independent of the electric field, strain engineering alters not only the intensity of optical peaks but also their position.

In this work, we construct the BlueP/ZrSSe heterostructure and explore systematically its electronic characteristics and interface features in the framework of first principles calculations. The stacking and electric field effects on the interface characters of BlueP/ZrSSe heterostructure are also considered. We find that the BlueP layer interacts with Janus ZrSSe layer via the weak van der Waals forces, which keeps the BlueP/ZrSSe heterostructure feasible. Both the BlueP/SZrSe and BlueP/SeZrS heterostructures possess indirect semiconductor and exhibits type-I band alignment. Furthermore, electric field can tune the band alignment and switch the BlueP/ZrSSe heterostructure from semiconductor to metal. These findings could provide a helpful guidance for using BlueP/ZrSSe heterostructure in practical applications of nanoelectronics and optoelectronics.

In this work, detailed investigations of the electronic and optical properties of a Janus Ga2STe monolayer under a biaxial strain and electric field have been performed using density functional theory. Via the phonon spectrum and ab-initio molecular dynamics simulations, the dynamical and thermal stabilities of the Janus Ga2STe monolayer are verified. Our obtained results showed that the Janus Ga2STe exhibits a direct semiconducting characteristic and its band gap depends greatly on the biaxial strain. While both the electronic and optical properties are very weakly dependent on the electric field, strain engineering can cause a direct–indirect band gap transitions in the Janus Ga2STe. At equilibrium, the optical absorbance of the Janus Ga2STe monolayer is activated in the infrared light region of about 0.9 eV, which is close to its band gap value. The main peak of the optical absorbance spectrum is located in the ultraviolet light region with an absorbance intensity of 11.914 × 104 cm−1 may be increased by compression strain. In particular, the absorbance intensity of the Janus Ga2STe monolayer increases rapidly in the visible light region, reaching 4.810 × 104 cm−1 and can be altered by strain. Our results not only show that the Janus Ga2STe monolayer has many promising applications in opto-electronic devices but also motivates experimental works on Janus structures in near future.

Combining different two-dimensional materials into layered van der Waals heterostructures are recently considered as an effective route to enhance the electronic properties of the constituent materials and to extend the application range in next-generation nanodevices. Here, the GeC/GaSe heterostructure and its electronic properties controlled by electric field have been constructed and systematically investigated using first-principles calculations. Five different stacking patterns of the GeC/GaSe heterostructure are constructed to consider the stacking effects on the electronic properties. We find that the GeC/GaSe heterostructure is mainly characterized by the weak van der Waals forces, dominating between GeC and GaSe layers, preserving their intrinsic properties in GeC/GaSe heterostructure. The GeC/GaSe heterostructure exhibits the type-II band alignment, where the electron–hole pairs are separated, making it suitable for fabricating next-generation optoelectronic nanodevices. Moreover, the stacking configurations have little affect the structural and electronic properties of the GeC/GaSe heterostructures. The pattern-I stacking configuration has the lowest binding energy and shortest interlayer distance as compared with other stacking patterns of the GeC/GaSe heterostructure. Furthermore, our results demonstrate that the electric field is considered as an effective route to modulate the electronic properties of GeC/GaSe heterostructure from semiconductor to metal. This finding makes the GeC/GaSe heterostructure promising material for optoelectronic nanodevices.

In this work, the electronic and optical properties of monolayer GaTe under biaxial strain and external electric field were investigated by density functional theory. Our calculated results indicate that the monolayer GaTe is an indirect-semiconductor with an energy gap of 1.41eV at equilibrium. Electronic properties of monolayer GaTe, especially the energy gap, depend greatly on the biaxial strain and external electric field. While the compressive strain slightly increases the energy gap, the tensile strain reduces quite rapidly the energy gap of the monolayer GaTe. In particular, semiconductor–metal phase transition can be observed when the external electric field was introduced. The GaTe monolayer strongly absorbs light in the ultraviolet region and the biaxial strain greatly changes its optical characteristics, especially the compression strain significantly increasing the absorption coefficient of the monolayer. Our results can provide more useful information for the prospect of application of the GaTe monolayer in next-generation optoelectronic devices.

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