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We report a first-principles, high-throughput search of X2YZ “Heuslerenes” generated by symmetry-guided exfoliation of their bulk Heusler parents. Calculated elastic tensors satisfy the 2D Born criteria, indicating mechanical stability as freestanding crystals. A deep-learning pipeline that embeds, classifies, and clusters the electronic band structures reveals three functionally distinct subsets: (i) 32 small-gap semiconductors with linear-band features alongside several half-metals exhibiting 100% spin polarization at the Fermi level, (ii) 98 compounds with noncollinear magnetic moments >1μB per formula unit, and (iii) 15 systems with ultra-low work functions, Φ < 3.0 eV, promising for spin filters, magnetoelectronics, and vacuum emitters. Topological diagnostics, parity eigenvalues, and Berry-curvature-based invariants reveal a diversity of nontrivial phases, including time-reversal invariant Z2 topological insulators and time-reversal symmetry breaking weakly magnetic Chern insulators; the latter include Rh2HfMg, which exhibits a large intrinsic anomalous Hall conductivity, σxy ≈ 285 S cm−1. Analysis of exciton absorption spectra within the framework of many-body perturbation theory and Bethe–Salpeter equations reveals large exciton binding energies, Eb > 2.3 eV, and possible excitonic insulator phases in other Rh-based Heuslerenes. Collectively, these results position Heuslerenes as a multifunctional 2D platform uniting robust magnetism, symmetry-protected topological transport, and excitonic tunability. More broadly, our symmetry-aware structure generation coupled with automated electronic, magnetic, and topological characterization defines an efficient workflow for designing quantum materials for next-generation spintronics and topological devices. 

A new generation of quantum material derived from intercalating zerovalent atoms such as Cu into the intrinsic van der Waals gap at the interface of atomically thin two-dimensional GeSe/SnS heterostructure is designed, and their optoelectronic features are explored for next-generation photovoltaic applications. Advanced ab initio modeling reveals that many-body effects induce intermediate band (IB) states, with subband gaps (~0.78 and 1.26 electron volts) ideal for next-generation solar devices, which promise efficiency greater than the Shockley-Queisser limit of ~32%. The charge carriers across the heterojunction are both energetically and spontaneously spatially confined, reducing nonradiative recombination and boosting quantum efficiency. Using this IB material in a solar cell prototype enhances absorption and carrier generation in the near-infrared to visible light range. Tuning the active layer’s thickness increases optical activity at wavelengths greater than 600 nm, achieving ~190% external quantum efficiency over a broad solar wavelength range, underscoring its potential in advanced photovoltaic technology. 

We report the mechanical properties of cubic boron nitride (c-BN) and diamond under the combined impact of dynamical pressure and temperature, calculated using ab initio molecular dynamics. Our study revealed a pronounced sensitivity of the mechanical properties of c-BN to applied pressure. Notably, c-BN undergoes a brittle-to-ductile transition at ∼220 GPa, consistent across various dynamical temperatures, while diamond exhibits no such transition. Furthermore, the Vickers hardness profile for c-BN closely mirrors that of diamond across a spectrum of temperature–pressure conditions, highlighting c-BN's significant mechanical robustness. These results underscore the superior resilience and adaptability of c-BN compared to diamond, suggesting its potential as an ideal candidate for applications in extreme environments. 

GeS and GeSe are 2D semiconductors with band gaps in the near infrared and predicted high carrier mobility. We find that excitation with 800 nm pulses results in long-lived free photocarriers, persisting for hundreds of picoseconds, in GeS and GeSe noribbons. We also demonstrate that zerovalent Cu intercalation is an effective tool for tuning the photoconductive response. Intercalation of ~ 3 atomic % of zerovalent Cu reduces the carrier lifetime in GeSe and GeS. In GeS, it also shortens the photoconductivity rise and improves carrier mobility.