Semiconductor saturable absorber mirror in the 3–5 µm mid-infrared region

• DOI: 10.1364/ol.444485
• Publication Date: 2022-01-03T17:32:49Z
• Authors: Zhipeng Qin; Xuliang Chai; Guoqiang Xie; Zhicheng Xu; Yi Zhou; Qi Wu; Jie Li; Zhuan Wang; Yuxiang Weng; Ting Hai; Peng Yuan; Jingui Ma; Jianxin Chen; Liejia Qian
• Keywords: ZBLAN; Saturable absorption; Mode-Locking

Semiconductor saturable absorber mirrors (SESAMs) have been regarded as a revolutionary technology for ultrafast mode-locked lasers, producing numerous landmark laser breakthroughs. However, the operating wavelength of existing SESAMs is limited to less than 3 µm. In this study, we create 3-5 µm mid-infrared (MIR) SESAM by engineering an InAs/GaSb type-II superlattice. Bandgap and strong coupling between potential wells in superlattice enable broadband response absorption spectral range. Using fabricated SESAM, realize Er:ZBLAN fiber at 3.5 µm, which delivers MIR ultrashort pulses with high long-term stability. The breakthrough fabrication will promote development coherent sources related application fields.