Amplification at 2.3-µm in 1.9-µm thulium-doped silica fiber laser Changshun Hou, Debasis Pal, Colin C. Baker, Tony Zhou, Daniel Rhonehouse, Jasbinder Sanghera and Johan Nilsson EPJ Web Conf., 307 (2024) 02045 Published online: 18 October 2024 DOI: 10.1051/epjconf/202430702045