We demonstrate robust single-transverse-mode light propagation in higher-order modes of a fiber, with effective area Aeff ranging from 2100 to 3200 μm2. These modes are accessed using long-period fiber gratings that enable higher-order-mode excitation over a bandwidth of 94 mm with greater than 99% of the light in the desired mode. The fiber is designed such that the effective index separation between modes is always large, hence minimizing in-fiber mode mixing and enabling light propagation over lengths as large as 12 m, with bends down to 4.5 cm radii. The modal stability increases with mode order, suggesting that Aeff of this platform is substantially scalable.
© 2006 Optical Society of AmericaPDF Article