Fig. 1. Experimental setup. (a) Structure of intensity difference squeezed state light source; (b) filter structure; (c) beam combiner structure; (d) structure of wavelength division multiplexer; (e) structure of grating differential detector; (f) structure of grating module

Fig. 2. Results of classic experiment. (a) Output power of amplified signal and generated idler under different pump power injection; (b) response of shot noise limit under different local light power; (c) fitting curve of shot noise under different local power; (d) response of intensity difference noise under different signal light gain

Fig. 3. Typical results of squeezing rate. (a) Typical results of squeezing rate at 20 MHz; (b) typical results of squeezing rate at 65 MHz

Fig. 4. Squeezing rate under different power seed light