γ-ray irradiation effect on the electrical transport properties of Cu films Zhaoguo Li, Dawei Yan, Zhiqiang Zhan, Jiangshan Luo, Zhiqing Wu, Fan Lei, Yudan He, Lei Jin, Bo Yang and Qiubo Fu Eur. Phys. J. B, 98 7 (2025) 140 Published online: 01 July 2025 DOI: 10.1140/epjb/s10051-025-00966-7