Experimental comparison of a Kerr nonlinearity figure of merit including the stimulated Brillouin scattering threshold for state-of-the-art nonlinear optical fibers

We introduce a new figure of merit (FOM) including the input pump power limit associated with stimulated Brillouin scattering (SBS) for evaluation of the Kerr nonlinearity efficiency of optical fibers. The new FOM is expressed as $\gamma L_{\mathrm{eff}}{P}_{\mathrm{SBS}}$ (γ is a nonlinearity parameter, $L_{\mathrm{eff}}$ is effective length, and $P_{\mathrm{SBS}}$ is the SBS threshold), while the conventional FOM is given by $\gamma L_{\mathrm{eff}}$. Using the new FOM, we perform an efficiency comparison among four types of state-of-the-art nonlinear optical fiber: a ${\mathrm{Bi}}_2{\mathrm{O}}_3$-based nonlinear fiber, a silica-based holey fiber, a highly nonlinear dispersion-shifted fiber, and a conventional dispersion-shifted fiber. The ${\mathrm{Bi}}_2{\mathrm{O}}_3$-based nonlinear fiber is found to have the best Kerr nonlinearity efficiency owing to the superior nonlinear property of the ${\mathrm{Bi}}_2{\mathrm{O}}_3$ glass compared with that of the silica.