Large effective mode field area single mode amplifier with exposure region in active quartz rod

[0014] Embodiment 1, a single-mode amplifier with a large effective mode field area in an active quartz rod, such as figure 1 , 2 , the amplifier includes: an active quartz rod, a pump source 4 . The structure of the active quartz rod is an exposure area 1 , an active quartz rod core 2 and an outer cladding 3 sequentially from inside to outside. The exposure area 1 is located in the center of the active quartz rod, and the refractive index of the exposure area 1, the active quartz rod core 2 and the outer cladding 3 decreases gradually.

[0015] The signal light source inputs the signal light to be amplified from the right end, and uses the pump source 4 to pump the right end surface.

[0016] The refractive index of the exposure area 1 was 1.459, and the radius of the exposure area 1 was 2.5 microns.

[0017] The refractive index of the active quartz rod core 2 is 1.455, and the radius of the active quartz rod core 2 is 5 mm. The refractive index of the outer cladding 3 is 1

[0018] Embodiment 2, a single-mode amplifier with a large effective mode field area in an active quartz rod with an exposure area, such as image 3 , the amplifier includes: an active quartz rod, a pump source 4 . The structure of the active quartz rod is an exposure area 1 , an active quartz rod core 2 and an outer cladding 3 sequentially from inside to outside. The exposure area 1 is located in the center of the active quartz rod, and the refractive index of the exposure area 1, the active quartz rod core 2 and the outer cladding 3 decreases gradually.

[0019] The signal light source inputs the signal light to be amplified from the right end, and uses the pump source 4 for side pumping.

[0020] The refractive index of the exposure area 1 was 1.457, and the radius of the exposure area 1 was 5 microns.

[0021] The refractive index of the active quartz rod core 2 is 1.454, and the radius of the active quartz rod core 2 is 50 mm. The refractive index of the outer cladding 3 i

[0022] Embodiment 3, a single-mode amplifier with a large effective mode field area in an active quartz rod with an exposure area, such as Figure 4 , the amplifier includes: an active quartz rod, a pump source 4 . The structure of the active quartz rod is an exposure area 1 , an active quartz rod core 2 and an outer cladding 3 sequentially from inside to outside. The exposure area 1 is located in the center of the active quartz rod, and the refractive index of the exposure area 1, the active quartz rod core 2 and the outer cladding 3 decreases gradually.

[0023] The signal light source inputs the signal light to be amplified from the right end, uses the pump source 41 for right end face pumping, and uses the pump source 42 for side pumping.

[0024] The refractive index of the exposure area 1 was 1.456, and the radius of the exposure area 1 was 10 microns.

[0025] The refractive index of the active quartz rod core 2 is 1.453, and the radius of the active quartz rod core 2 is