Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · 2610.14908

Pressure-Driven Evolution of the Physical Properties of Layered Y2GaB and Y2InB MAB Phases: A Comparative First-Principles Study

M. Rabi Us Sani Shapon·Md. Asif Afzal·Jubair Hossan Abir·Raihana Shams Islam·Saleh Hasan Naqib
View original source ↗Read source document ↗Export metadata ↓

Abstract

MAB phases are nanolaminated ternary borides in which strong in-plane M-B bonds and weaker interlayer interactions drive their distinctive stability and functionality. Hydrostatic pressure offers a direct route to tune the in-plane and interlayer interactions that govern the stability and functionality of layered Y2GaB and Y2InB borides. Here, first-principles calculations are used to compare their structural, elastic, thermophysical, electronic, bonding, optical, and vibrational responses from 0 to 20 GPa. Elastic criteria show that Y2GaB is stable at 0, 5, and 10 GPa, whereas Y2InB is stable only at ambient pressure. Within the stable Y2GaB range, compression increases the elastic moduli, acoustic velocities, Debye temperature, and lattice thermal conductivity while reducing the elastic anisotropy. Both compounds are multiband metals and spin-orbit coupling modifies local dispersions without opening a gap. Y2GaB retains nine Fermi-surface sheets from 0 to 10 GPa, whereas Y2InB has eight at ambient pressure, with no pressure-induced topological reconstruction. Charge-density and overlap analyses indicate mixed ionic-covalent Y-B bonding within a delocalized metallic background. Optical parameters are anisotropic. Unit-cell phonon spectra contain positive frequencies at 0 and 10 GPa, although expanded-supercell calculations reveal low-frequency sensitivity. These results establish mechanically viable pressure windows and clarify substitution-driven structure-property relationships for these borides.

Explore related subjects

cond-mat.mtrl-sci

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

M. Rabi Us Sani Shapon, Md. Asif Afzal, Jubair Hossan Abir, Raihana Shams Islam, Saleh Hasan Naqib. 2026-10-10. Pressure-Driven Evolution of the Physical Properties of Layered Y2GaB and Y2InB MAB Phases: A Comparative First-Principles Study. https://arxiv.org/abs/2610.14908

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Magnetic Structures Database from Symmetry-aided High-Throughput Calculations

Magnetic structures-the spatial arrangement of magnetic moments-underpin the diverse functionalities of magnetic materials, yet they have been experimentally determined for only a small fraction of known compounds. Conventional first-principles prediction requires candidate magnetic configurations as input, but the number of possible configurations is in principle infinite. Although the classic Landau-theory based symmetry analysis is widely used to classify magnetic ordering, their direct application to generate input magnetic configurations remains a major challenge due to unavoidable residual degrees of freedom. Here we turn this classification language into a practical predictive framework by resolving these freedoms through a two-step symmetry-aided strategy: an irrep-compatible maximal-magnetic-subgroup selection, followed by the physically motivated high-symmetry-direction construction. This highly efficient scheme is justified within the newly developed oriented spin space group framework. Benchmarked against 1,043 Landau-compatible experimental structures in MAGNDATA, our candidate sets reproduce 90% of the experimentally reported magnetic structures in the four high-symmetry crystal systems with only ~51 candidates per material on average, and subsequent first-principles calculations with material-specific Hubbard U parameters recover the experimental ground state with 83% accuracy. Applying the validated workflow to 19,808 transition-metal compounds, we construct a database of more than 5,000 magnetic materials-nearly twice the size of the experimental MAGNDATA. The database reveals statistical regularities accessible only at scale, including the occurrence rate of magnetism, the prevalence of competing magnetic states, and enables the identification of hundreds of magnetic topological materials, altermagnets, and other emerging magnetic phases and functionalities.

cond-mat.mtrl-sci↗
arXiv2026

Vacancy-Enhanced $N-N$ Bonding and Deep Level Complex Defect Formation in $β-Ga_2O_3$

Nitrogen implantation can make $β-Ga_2O_3$ semi-insulating, but the atomic origin responsible for carrier trapping remains unresolved. Here, hybrid density functional theory is used to examine complexes derived from an interstitial-substitutional N pair, $N_{i9}-N_{OI}$, and effects of nearby O and Ga vacancies on $N-N$ bonding, stability, and electronic states. Within the configurations examined, N atoms favor co-localization. In selected Ga-vacancy-assisted complexes, the $N-N$ distance shortens to 1.09-1.19 $\mathring{\mathrm{A}}$ and exhibits electron localization consistent with substantial $N-N$ covalent character. Positive binding energies indicate favorable association relative to separated defects, although many of these complexes have high formation energies and are therefore more likely to be metastable products of implantation than abundant equilibrium defects. Calculated N $K$-edge XANES spectra for two selected Ga-defect-assisted $N-N$ complexes reveal a pronounced sensitivity of the near-edge $π^*$ resonance to the local defect environment, providing an atomistic perspective on the experimentally observed evolution toward molecular $N_{2}$ during annealing. Projected densities of states and spin-density distributions show localized N-$2p$- and O-$2p$-derived states well inside the band gap. These vacancy-assisted N complexes therefore provide an atomistic mechanism for deep carrier trapping and current blocking rather than shallow acceptor doping in $β-Ga_2O_3$.

cond-mat.mtrl-sci↗
arXiv2026

Dynamic Magnetic Pair-Density Function of a One-Dimensional Ferromagnet

The dynamic magnetic pair-density function (DymPDF) $D_{\rm M}(r, E)$ is derived by extending the static magnetic pair distribution function (mPDF) to finite energy transfer. The analytical DymPDF of a one-dimensional Heisenberg ferromagnet is obtained from the magnon dispersion and compared with simulations performed using {\textsc SpinW}. Excellent agreement is achieved for energy dependence of the nearest-neighbor spin-pair correlation, demonstrating that the DymPDF changes sign at the magnon-mode transition occurring at one-half of the maximum magnon energy. The r-dependence of DymPDF at low energy is also reproduced with a model including magnon correlation length and Fourier-termination effects. These results establish the theoretical foundation of DymPDF analysis for investigating local spin dynamics in magnetic materials.

cond-mat.mtrl-sci↗