33.1 nm Wide-Tuning High-Power Blue-Green Semiconductor Disk Laser and Its Application in Underwater Wireless Optical Communication with Various Water Types

Due to the unique wavelength characteristics, blue-green laser sources have shown broad application prospects across multiple fields. In this work, a wide-tuning high-power blue-green semiconductor disk laser based on a dual-gain-chip architecture was reported. A composite resonator was constructed by integrating two plano-concave V-shaped subcavities that share a common birefringent filter. Intracavity frequency doubling was implemented using a type-I phase-matched LBO crystal, enabling a continuous tuning range of 33.1 nm from 484.5 to 517.6 nm and a maximum output power of 12.43 W. In addition, underwater wireless optical communication (UWOC) experiments were conducted in pure seawater, clear seawater, and coastal seawater using the four wavelengths 486 nm, 495 nm, 507 and 515 nm in combination with acoustic-optical modulation (AOM) technology. At a transmission distance of 15 m and a data rate of 30 Mbps, the bit error rate (BER) in all three water types remained below the forward error correction (FEC) threshold (3.8 × 10–3). The optimum communication performance was achieved at 486 nm in pure seawater (BER = 1.42 × 10–3), 515 nm in clear ocean water (BER = 1.45 × 10–3), and at 515 nm in coastal seawater (BER = 1.25 × 10–3). These results demonstrate that flexible wavelength tuning enables the laser source to maintain reliable communication performance across different water environments, thereby overcoming the limited adaptability of conventional single-wavelength systems to complex marine conditions. The demonstrated blue-green laser sources show great potential for wavelength-adaptive underwater wireless optical communication in diverse oceanic environments.