Tunable erbium-doped fiber ring laser with a polymer micro bottle resonator

A new tunable fiber laser structure based on an erbium-doped fiber ring laser (FRL) and a polymer-based microbottle resonator (PMBR) as the wavelength selective filter is proposed and demonstrated. The tunability of the laser output in response to axial strain of up to 253.6 με applied to the PMBR is demonstrated experimentally. When the strain was applied to the PMBR’s long axis, the central lasing wavelength shifted towards shorter wavelengths in a linear fashion. The laser's strain sensitivity was determined to be 0.69 pm/με. The proposed strain-tunable PMBR laser offers the advantages of simple structure, low cost, robust performance, and has the potential for applications in sensing and tunable micro lasers.