Numerical Simulation of High-Power Optical Amplifiers at 2.3 μm Based on a Special Multicore Fiber

The development of high-power laser sources at 2.3 & mu;m is highly demanded for remote sensing and other applications. However, this wavelength is poorly covered by present-day lasers. To obtain 100 W class high-power radiation at 2.3 & mu;m, we propose to use simultaneously cascade laser amplification at 2 and 2.3 & mu;m with a commercially available diode pump at 793 nm and stimulated Raman scattering between the amplified signal waves in a special zinc-tellurite multicore fiber with ten trivalent-thulium-ion-doped cores arranged in a ring. We demonstrate numerically that the use of an out-of-phase supermode (with spatial phases differing by & pi; in neighboring cores) can provide up to 50% efficiency conversion from the 793 nm pump to the 2.3 & mu;m wave.

Automated summary

The development of high-power 2.3 & mu;m laser sources is in great demand for remote sensing and other applications. To achieve high-power radiation at this wavelength, a cascade laser amplification technique at 2 and 2.3 & mu;m, using a diode pump at 793 nm and stimulated Raman scattering in a zinc-tellurite multicore fiber with trivalent-thulium-ion-doped cores, is proposed. Numerical simulations show that an out-of-phase supermode can efficiently convert the 793 nm pump to the 2.3 & mu;m wave, with a conversion efficiency of up to 50%.