Design of resonant cavity for linear cavity single frequency fiber laser based on temperature controlled Fiber Bragg grating

In response to the limited tuning ability of traditional linear cavity single frequency fiber lasers caused by fixed cavity length and static feedback mechanism, a resonant cavity design for linear cavity single frequency fiber lasers based on temperature controlled fiber gratings is proposed. It achieves synergistic improvement in linewidth compression, power stability, and tuning range through thermal optical coupling modeling and intelligent algorithm collaborative search. The experimental results show that the average line width of the proposed scheme is 0.86 Hz (compared to 1.97 Hz and 1.59 Hz in the comparative scheme), the average tuning range is 38.0 nm (compared to 22.3 nm and 12.5 nm in the comparative scheme), and the average steady-state temperature control error is 0.81 °C (compared to 2.08 °C and 1.74 °C in the comparative scheme). Its average anti vibration offset is 0.75 kHz/g (compared to 2.67 kHz/g and 1.86 kHz/g in the comparative scheme), and its average photoelectric conversion efficiency is 57.60% (compared to 48.85% and 52.24% in the comparative scheme). In addition, the average floating-point computational cost of this scheme is 30.9 G (compared to 65.4 G and 40.7 G in the comparison scheme), the average running energy consumption is 13.1 W•h (compared to 66.9 W•h and 34.7 W•h in the comparison scheme), and the average memory usage is 24.92% (compared to 44.3% and 39.62% in the comparison scheme). It outperforms the comparative scheme in key indicators. The proposed dynamic tuning and multi-objective optimization platform can enhance the comprehensive performance boundary of lasers in complex environments, providing a highly stable light source design solution for precision spectral measurement, high-resolution sensing, and quantum communication fields.