Channel capacity of small modular quantum networks in the ultrastrongly coupled regimeSalvatore Alex Cordovana, Luigi Giannelli, Nicola Macrì, Giuliano Benenti, Elisabetta Paladino and Giuseppe A. FalciEur. Phys. J. Spec. Top., 235 11 (2026) 2755-2760DOI: https://doi.org/10.1140/epjs/s11734-025-02020-0