Robust-fidelity high-dimensional controlled-controlled-SUM gate with qudits Fang-Fang Du, Xin-Shan Du, Zhuo-Ya Bai, Qiang Zhu and Qiu-Lin Tan EPJ Quantum Technol., 12 1 (2025) 95 Published online: 06 August 2025 DOI: 10.1140/epjqt/s40507-025-00398-3