Adsorption of N, He and Ne on CGe nanoribbons for sensing and optoelectronic applications.

Research into nanomaterials yields numerous exceptional applications in contemporary science and technology. The subject of this investigation is a one-dimensional nanostructure, six atoms wide, featuring hydrogen-functionalized edges. The theoretical foundation of this study relies on Density Functional Theory (DFT) and is executed through the utilization of the Vienna Ab initio Simulation Package (VASP). The outcomes demonstrate the stability of adsorption configurations, along with the preservation of a hexagonal honeycomb lattice. The pristine configuration, characterized by a wide bandgap, is well-suited for optoelectronic applications, whereas adsorption configurations find their application in gas sensing. Nitrogen (N) adsorption transforms the semiconducting system into a semimetallic one, with the spin-up state showing semiconductor characteristics and the spin-down state exhibiting metallic attributes. The intricate multi-orbital hybridization is explored through the analysis of partial states. While the pristine system remains non-magnetic, N adsorption introduces a magnetic moment of 0.588 µB. The examination of charge density differences indicates a significant charge transfer from N to the CGe substrate surface. Optical properties are systematically investigated, encompassing the dielectric function, absorption coefficient and electron-hole density. Notably, the real part of the dielectric function exhibits negative values, a result that holds promise for future communication applications.

C, Ge-doped h-BN quantum dot for nano-optoelectronic applications.

Emerging materials, particularly nanomaterials, constitute an enduring focal point of scientific inquiry, with quantum dots being of particular interest. This investigation is centered on elucidating the exceptional structural, electromagnetic, and optical characteristics of hexagonal boron nitride (h-BN) quantum dots and h-BN quantum dots doped with carbon (C) and germanium (Ge). The employed methodology in this study hinges on density functional theory coupled with the Vienna Ab initio simulation package. The outcomes of this research unveil the structural stability of hexagonal honeycomb structures upon optimization. Comprehensive examinations encompassing structural properties, electromagnetic characteristics, and charge density variations have been systematically conducted. Furthermore, this work delves into the elucidation of multi-orbital hybridizations that give rise toσbonds andπbonds. Notably, the outcomes of the optical property analysis divulge intriguing observations. Specifically, the absorption coefficient exhibits zero values within select energy ranges within the visible light spectrum, a phenomenon observed in both pristine and C-doped configurations. This discovery underscores the material's optical transparency at these specific radiation energies. Additionally, the 0xand 0ycomponents of the dielectric function display negative values across particular energy ranges, a characteristic that holds significant promise for potential applications in nanotechnology communications, offering minimal energy loss.

Investigation of Be, Mg, Ti-adsorbed boron-germanene nanoribbons for nano applications.

One-dimensional systems are nanostructures of significant interest in research due to their numerous potential applications. This study focuses on the investigation of one-dimensional boron-germanene nanoribbons (BGeNRs) and BGeNRs doped with Be, Mg, and Ti. Density functional theory combined with the Vienna Ab initio Simulation Package forms the foundation of this research. The electromagnetic and optical properties of these structures are systematically examined. The findings reveal that all the studied structures exhibit metallic behaviour, with differences in their magnetic properties. The magnetic moments of the pristine and Be-doped structures are both zero, whereas the Mg and Ti-doped structures exhibit magnetic moments of 0.012µBand 2.234µB, respectively. Partial density of states (PDOS) analyses highlight the contributions of various elements and the complex multi-orbital hybridization among them. The optical properties are investigated through the real and imaginary parts of the dielectric function, along with the absorption coefficient and electron-hole density. This study indicates potential applications in adsorption sensors, the modulation of system magnetism via adsorption, and information transmission technologies.

Electrical and optical properties of C, Ge-doped armchair silicene nanoribbons applied in optoelectronics.

With the continuous development of nanotechnology, the search for new material structures plays a crucial role. Silicene nanoribbons (SiNRs) are one-dimensional materials that hold promise for numerous potential applications in the future. The electric and optical properties of C, Ge-doped armchair SiNRs are investigated in this study using density functional theory. All the doped configurations are stable and maintain the honeycomb hexagonal structure after optimization. Doping with C yields flatter structures, while doping with Ge yields larger buckling heights. The C 1-1 doping configuration is highlighted because its band gap is extended up to 2.35 eV, making it an ideal candidate for potential optoelectronic applications. The charge distribution, charge density difference, and hybridization of multiple orbitals are also systematically studied. The optical properties reveal the differences between C and Ge doping, with a clear anisotropy observed. Strong absorption occurs at high electromagnetic wave energies, while the absorption coefficient rapidly decreases in the long-wavelength range. The study of electron-hole density shows good agreement with the energy band structure, where electron-hole pairs only exist when the excitation energy is greater than the bandgap width, and not all excitation energy values give rise to electron-hole pairs. This study contributes a small part to creating potential applications in nanotechnology.