A high power fiber laser system emitting a substantially diffraction limited beam with a Gaussian intensity profile includes a single mode (“SM”) neodymium fiber pump source outputting a SM pump light; a seed laser operative to emit a SM signal light at a wavelength greater than that of the pump light; a SM DWM receiving and multiplexing the SM pump and signal lights. The disclosed system further includes a booster fiber amplifier which is configured with a frustoconically-shaped ytterbium (“Yb”) doped core receiving the pump and signal lights and configured with a small diameter input end which supports only a SM and a large diameter output end which is capable of supporting the SM and high order modes (:HOM”). The booster further has a cladding surrounding and coextending with the core, the core being configured for having intensity profiles of respective SMs of pump and signal lights overlap one another so that an overlap integral substantially equals to one (1) along an entire length of the core. The SM of the light signal extracts substantially the entire energy from the pump mode leaving the HOMs without amplification necessary to affect a quality of the diffraction limited beam of the system in a MW peak power range and hundreds of watt average power range.

Neodymium decreased 8,500 CNY/MT or 2.35% since the beginning of 2020, according to trading on a contract for difference (CFD) that tracks the benchmark market for this commodity. Historically, Neodymium reached an all time high of 715000 in June of 2012. Neodymium is the strongest permanent magnet material yet discovered. It is widely used in microphones, professional loudspeakers, headphones, computer hard disks, electric motors and generators. It is a rare-earth mineral mostly extracted in China, the United States, Brazil, India, Sri Lanka, and Australia.