Nuclear optical clocks, a novel type of optical clock, align well with future development trends of optical clocks. As the core material for developing solid-state nuclear optical clocks, it is important to study Th-doped crystals with comprehensive advantages for the advancement of this field. The nonlinear crystal $\mathrm{Sr}{\mathrm{B}}_4{\mathrm{O}}_7$ (SBO) can directly frequency double a 296.8 nm laser to generate 148.4 nm excitation light, which matches the nuclear transition band of ${}^{229}\mathrm{Th}$. Meanwhile, SBO can be used as a host crystal for Th doping. This study reports the successful growth of Th-doped SBO, achieving the doping of thorium in a nonlinear oxide host. A 1-mm-thick Th:SBO crystal ($1.04\times {10}^{18}\mathrm{c}{\mathrm{m}}^{-3}$) retained high VUV transmittance at 148.4 nm (52.08%), only marginally lower than SBO (57.29%). Th:SBO crystal is expected to be a promising candidate for solid-state optical nuclear clocks.

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• Atomic, optical & lattice clocks
• Chemical binding
• Electron correlation calculations for atoms & ions
• Density functional theory