Research on saturable absorption characteristics of 2D WS₂/MoS₂ and its optimization for OPO operation

In this study, a preparation method for few-layer WS₂/MoS₂ thin films is introduced. The as-fabricated nanosheets are comprehensively characterized, and their nonlinear transmittance is systematically tested. A dual-loss Q-switching scheme is successfully implemented to pump a KTP-intracavity optical parametric oscillator (KTP-IOPO). The laser output characteristics, including average output power, pulse width, single-pulse energy, and peak power, are analyzed for both acousto-optic (AO) single Q-switching and AO combined with WS₂/MoS₂ dual Q-switching configurations under laser-pumped KTP-IOPO conditions. The influence of pump power variations on these characteristics is thoroughly investigated. Additionally, the spectra of the fundamental and signal lights, as well as the stability of the output pulse sequences, are measured and analyzed.