Many-body signatures of dimensional reduction in quasi-one-dimensional ZrS 3
Anonymous, Letizia Chiodo
The electronic and optical properties of quasi-one-dimensional transition-metal trichalcogenides remain largely unexplored beyond the mean-field approximation, and it is not clear how they evolve as the crystal is thinned. By performing first-principles many-body perturbation theory calculations, we determine the quasiparticle band structures and the polarization-resolved optical response of ZrS 3 in the bulk, bilayer, and monolayer limits, using a hierarchy of methods (hybrid DFT, G W , and the Bethe-Salpeter equation). We find that all three systems are indirect-gap semiconductors with a quasidirect character, the direct-indirect splitting being δ ≈ 0.10 – 0.13 eV and nearly independent of both the level of theory and the dimensionality. The mean-field gaps are almost insensitive to thickness, whereas the quasiparticle corrections increase the gap by ≈ 0.9 eV from bulk to monolayer. The effective exact-exchange fraction reproducing the G W gap scales as α ∼ ɛ ∞ − 1 , increasing from ≈ 0.19 to ≈ 0.33 , so that no single hybrid functional describes the full dimensional series. The optical onset blueshifts monotonically ( ≈ 2.4 → 2.8 → 3.0 eV ) and the near-edge absorption is strongly dichroic. A change in light polarization does not simply shift the excitonic resonance ( ≈ 0.09 eV ); it also reorganizes the underlying excitonic wave function, selecting distinct band channels and k -space regions. A real-space, participation-ratio analysis resolves moderately delocalized, Wannier-Mott-like excitons templated along the covalent chains. They are predominantly sulfur-derived (75%–88% of the density on sulfur for the chain-polarized bulk states), which identifies them as ( S 2 ) 2 − disulfide excitations rather than S → Zr charge-transfer states, while in the bilayer the electron delocalizes across both layers, the real-space imprint of interlayer screening. These results provide a consistent reference for the quasiparticle and excitonic energy scales of ZrS 3 from the bulk to the few-layer limit.
Physical review. B./Physical review. B•Oct 1, 2026•0 citations