Er-doped fiber comb with enhanced f(ceo) S/N ratio using Tm:Ho-doped fiber

Abstract

We report that the Tm:Ho-doped fiber can be utilized to improve the frequency stabilization of the Er-doped fiber comb. This rare-earth doped fiber provides photon absorption at 1.2 mu m and 1.7 mu m wavelengths together with emission at wavelengths between 1.8 mu m to 2.1 mu m. This unique combination of the absorption and emission regions constructively redistributes the spectral power of the supercontinuum generated by a highly nonlinear fiber to detect the carrier-envelope-offset frequency (f(ceo)) via a self-referencing f-2f interferometer. As a result, the signal to noise (S/N) ratio of the detected f(ceo) signal increases by 10 dB, thereby increasing the potential of enhancing the long-term frequency stability of the fiber frequency comb. (c) 2009 Optical Society of America