Fig. 1. Schematic diagram of using PZT stretching mechanism to generate axial tension acting on the whole DBR fiber for frequency tuning of DBR fiber laser

Fig. 2. Maximum no-jump mode tuning range obtained at different controlled temperatures. (a) Laser frequency variation recorded by a wavelength meter during the process of driving the PZT stretching mechanism with a sawtooth wave signal when the controlling temperature is 35 ℃; (b) the frequency tuning range without mode hopping of the laser as a function of the controlling temperature

Fig. 3. Frequency tuning response characteristics for the laser controlled at different temperatures. (a) 15 ℃; (b) 40 ℃; (c) 60 ℃

Fig. 4. Measured laser output characteristics with the PZT driving voltage of 10 V (red), 30 V (blue), and 69 V (green). (a) Output laser linewidth; (b) relative intensity noise; (c) spectral variation curve; (d) measured output powers of the laser (blue) and fiber amplifier (red) as functions of the voltage of PZT driven by a 2 mHz, 69 V sawtooth wave signal (green)