600 nm-Wide Band ASE Optical Source Exploiting a Tm:Er:Yb:Ho Co-Doped Germanate Fiber

In this paper, the numerical model of a 980-nm pumped optical fiber source exploiting the amplified spontaneous emission (ASE) phenomenon is illustrated. The device is based on a Tm:Er:Yb:Ho co-doped germanate fiber and allows incoherent light emission in the 1500-2100 nm wavelength range. The model exploits the rate equations approach and takes into account the energy transfer phenomena between different rare earths. Several simulations are performed in order to identify the best dopant concentrations for extending the output ASE spectrum as much as possible. By employing a 1 m-long optical fiber, with an input pump power of 0.3 W, an ASE spectrum covering a band of about 600 nm with a total output power of over 15.8 mW is predicted.