The electronic band structures of hexagonal ZnO and cubic ZnS, ZnSe, and ZnTe compounds are determined within hybrid-density-functional theory and quasiparticle calculations. It is found that the band-edge energies calculated on the [Formula: see text] (Zn chalcogenides) or GW (ZnO) level of theory agree well with experiment, while fully self-consistent QSGW calculations are required for the correct description of the Zn 3d bands. The quasiparticle band structures are used to calculate the linear response and second-harmonic-generation (SHG) spectra of the Zn-VI compounds. Excitonic effects in the optical absorption are accounted for within the Bethe-Salpeter approach. The calculated spectra are discussed in the context of previous experimental data and present SHG measurements for ZnO.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1088/1361-648X/aa6b2a | DOI Listing |
Sci Rep
January 2025
School of Advanced Technologies, Iran University of Science and Technology, Tehran, 1684613114, Iran.
This study presents a very thin wideband linear polarization converter in transmission mode with near-unity conversion efficiency. The suggested converter consists of a periodic array on a single-layer substrate, two metallic layers and six vias. Metallic vias connect the upper and lower layers of the construction.
View Article and Find Full Text PDFNat Commun
January 2025
National Laboratory of Solid-State Microstructures, Collaborative Innovation Center of Advanced Microstructures, School of Physics, Nanjing University, Nanjing, China.
In flat-band systems, emergent physics can be substantially modified by the presence of another nearby electronic band. For example, a Mott˘Hubbard insulator can turn into a charge transfer insulator if other electronic states enter between the upper and lower Hubbard bands. Here, we introduce twisted double bilayer (TDB) WSe, with twist angles near 60°, as a controllable platform in which the K-valley band can be tuned to close vicinity of the Γ-valley moiré flat band.
View Article and Find Full Text PDFNat Commun
January 2025
Key Laboratory of Advanced Photonic and Electronic Materials, Key Laboratory of Optoelectronic Devices and Systems with Extreme Performances of MOE and School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China.
The incorporation of thermal dynamics alongside conventional optoelectronic principles holds immense promise for advancing technology. Here, we introduce a GaON/GaN heterostructure-nanowire ultraviolet electrochemical cell of observing a photothermoelectric bipolar impulse characteristic. By leveraging the distinct thermoelectric properties of GaON/GaN, rapid generation of hot carriers establishes bidirectional instantaneous gradients in concentration and temperature within the nanoscale heterostructure via light on/off modulation.
View Article and Find Full Text PDFNat Commun
January 2025
DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE), Department of Chemistry, Indian Institute of Technology, Madras, Chennai, 600036, India.
We report the synthesis of [Ag(o-CBT)] abbreviated as Ag, a stable 8e⁻ anionic cluster with a unique Ag@Ag@Ag core-shell structure, where o-CBT is ortho-carborane-1-thiol. By substituting Ag atoms with Au and/or Cu at specific sites we created isostructural clusters [AuAg(o-CBT)] (AuAg), [AgCu(o-CBT)] (AgCu) and [AuAgCu(o-CBT)] (AuAgCu). These substitutions make systematic modulation of their structural and electronic properties.
View Article and Find Full Text PDFACS Nano
January 2025
Department of Chemistry, University of California Berkeley, Berkeley, California 94720, United States.
Understanding charge transport in semiconductor quantum dot (QD) assemblies is important for developing the next generation of solar cells and light-harvesting devices based on QD technology. One of the key factors that governs the transport in such systems is related to the hybridization between the QDs. Recent experiments have successfully synthesized QD molecules, arrays, and assemblies by directly fusing the QDs, with enhanced hybridization leading to high carrier mobilities and coherent band-like electronic transport.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!