Beyond diamond: Interpretable machine learning reveals design principles for quantum defect host materials
Phys. Rev. Materials 10, 056201 – Published 11 May, 2026
DOI: https://doi.org/10.1103/bt3b-hp18
Abstract
Solid-state spin defects in wide-band-gap semiconductors are leading candidates for quantum information processing, but systematic identification of suitable host materials remains limited by the cost of first-principles screening across vast chemical spaces. We address this with a composition-only machine learning framework built on heterogeneous Rashomon set ensembles: by contrasting the feature attributions of seven diverse classifiers, we extract consensus design rules that no single model identifies alone—filled valence -, -, and shells, low chemical heterogeneity, and enrichment in C, S, Si, and O favor quantum compatibility. Screening thermodynamically stable compounds, we identify 122 high-confidence candidates (confidence ), recovering most experimentally verified hosts (C, , and ) and predicting unexplored materials including , and layered chalcogenides (). Density-functional perturbation theory calculations on 12 representative materials validate dielectric screening as a coherence proxy ( against experimental ), and vacancy calculations for reveal deep, isolated midgap states favorable for spin-defect hosting. The framework provides transferable, physically grounded design principles for rational quantum materials discovery beyond traditional carbide and nitride hosts.