Fiber amplifier having a non-doped inner core and at least one doped gain region

摘要

A fiber amplifier includes at least one longitudinally extending non-doped inner core capable of transmitting signals. At least partially surrounding the inner core and extending at least partially therealong, the fiber amplifier also includes at least one gain region capable of amplifying signals propagating therethrough. The fiber amplifier also includes an outer core surrounding the gain region and the inner core and extending longitudinally therealong. The outer core is capable of transmitting pump energy such that the pump energy at least partially amplifies signals propagating through the inner core according to a nonlinear amplification process, such as a Raman or a Brillouin amplification process.