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In this computational study, density functional theory (DFT) is employed to analyze the structural, electronic, elastic, and topological properties of ternary compounds MXY (M = Ti, Sn, Ir, X = Se, Te, Y = Se, Te). The effects of spin–orbit interaction and pressure‐induced strain are investigated to understand their influence on the stability, mechanical properties, and electronic behavior, paving the way for potential technological applications. The findings confirm that these compounds are inherently stable in nonmagnetic phases, with spin–orbit interaction critically influencing their energy–volume landscapes. The calculated lattice parameters, ratios of lattice constants, and bulk moduli closely align with existing data, confirming the reliability of our approach. Mechanical assessments reveal distinct behaviors: IrSe₂exhibits the highest stiffness due to pronounced covalent bonding, contrasting with SnTe₂'s elastic anisotropy and SnSeTe's nearly isotropic properties. Electronically, most compounds show metallic characteristics, except SnSe₂, which behaves as a semiconductor with an indirect, pressure‐sensitive energy bandgap. Topological analysis under varying hydrostatic pressures indicates band inversions in TiSe₂, IrSe₂, and SnSeTe, suggesting topological phase transitions absent in other compounds. This study enriches our understanding of these materials and refines the application of DFT in material design.

This study investigates the entanglement properties of quantum dots (QDs) under a universal Hamiltonian where the Coulomb interaction between particles (electrons or holes) decouples into charging energy and exchange coupling terms. Although this formalism typically decouples the charge and spin components, confinement‐induced energy splitting can induce unexpected entanglement within the system. By analyzing the dynamic susceptibility and quantum Fisher information (QFI), significant behaviors are uncovered influenced by exchange constants, temperature variations, and confinement effects. In QDs with Ising exchange interactions, far below the Stoner instability (SI) point, where the QD is in a disordered paramagnetic phase, temperature reductions lead to decreased entanglement, challenging conventional expectations. These findings demonstrate that for QDs with small exchange interactions, the responses of easy‐plane () and easy‐axis () configurations are similar, with increased anisotropy broadening susceptibility and shifting its maximum to higher frequencies. For large exchange interactions, the susceptibility differences between easy‐plane and easy‐axis QDs become significant, with easy‐plane QDs exhibiting a higher susceptibility magnitude. Additionally, the study reveals that temperature variations affect the dynamic response functions differently in easy‐axis and easy‐plane QDs. In easy‐plane QDs, QFI consistently decreases with increasing temperature, whereas in easy‐axis QDs, QFI behavior is highly dependent on the strengths of and , showing either an increase or decrease with temperature based on specific coupling conditions. Conversely, at low temperatures, anisotropic Heisenberg models exhibit enhanced entanglement near isotropic points. Overall, this work contributes to advancing the understanding of entanglement in QDs and its potential applications in quantum technologies.

This paper investigates the microscale engineering aspects of n-type doped GaSb to address the challenges associated with achieving high electrical conductivity and precise dopant distribution in this semiconductor material. AC impedance spectroscopy is employed as a reliable technique to characterize the microstructural and electrical properties of GaSb, providing valuable insights into the impact of grain boundaries on overall electrical performance. The uneven distribution of dopants, caused by diffusion, and the incomplete activation of introduced dopants pose significant obstacles in achieving consistent material properties. To overcome these challenges, a careful selection of alloying elements, such as bismuth, is explored to suppress the formation of native acceptor defects and modulate band structures, thereby influencing the doping and compensator formation processes. Additionally, the paper examines the effect of microwave annealing as a potential solution for enhancing dopant activation, minimizing diffusion, and reducing precipitate formation. Microwave annealing shows promise due to its rapid heating and shorter processing times, making it a viable alternative to traditional annealing methods. The study underscores the need for a stable grain boundary passivation strategy to achieve significant improvements in GaSb material performance. Simple grain size reduction strategies alone do not result in better thermoelectric performance, for example, and increasing the grain boundary area per unit volume exacerbates the issue of free carrier compensation. These findings highlight the complexity of achieving optimal doping in GaSb materials and the importance of innovative analytical techniques and controlled doping processes. The comprehensive exploration of n-type doped GaSb presented in this research provides valuable insights for future advancements in the synthesis and optimization of high-conductivity nanostructured n-type GaSb, with potential applications in thermoelectric devices and other electronic systems.