SILVA, DIEGO S. daWETTER, NIKLAUS U.KASSAB, LUCIANA R.P.ROSSI, WAGNER deARAUJO, MARIANA S. de2019-12-032019-12-032020SILVA, DIEGO S. da; WETTER, NIKLAUS U.; KASSAB, LUCIANA R.P.; ROSSI, WAGNER de; ARAUJO, MARIANA S. de. Double line waveguide amplifiers written by femtosecond laser irradiation in rare-earth doped germanate glasses. <b>Journal of Luminescence</b>, v. 217, p. 1-5, 2020. DOI: <a href="https://dx.doi.org/10.1016/j.jlumin.2019.116789">10.1016/j.jlumin.2019.116789</a>. Disponível em: http://repositorio.ipen.br/handle/123456789/30417.0022-2313http://repositorio.ipen.br/handle/123456789/30417We report the production of active double waveguides in Er/Yb doped GeO2-PbO glasses, by direct femtosecond laser writing. The glasses were produced using the melt-quenching technique and the active waveguides were written using 30 fs laser pulses, at 800 nm, with writing speed of 0.06 mm/s and pulse energy of 32 μJ. The photo-induced negative refractive index change was of 􀀀 7.4 � 10􀀀 3. The Er/Yb doped sample showed a relative gain (signal enhancement of 7.5 dB/cm, for 105 mW of 980 nm pump power. The relative gain compensates both, the propagation losses and the absorption losses, and a positive maximum internal gain of 4.6 dB/cm can be obtained at the signal wavelength of 1550 nm. The results obtained in present work demonstrate that Er/Yb glasses are promising materials for the fabrication of integrated amplifiers, lossless components and lasers based on germanate glasses.1-5openAccesslaser spectroscopyoptical systemsamorphous staterare earthsgermanatesdoped materialsglasslaser radiationwaveguidesArtigo de periódico21710.1016/j.jlumin.2019.1167890000-0003-1371-75210000-0002-9379-9530https://orcid.org/0000-0003-1371-7521https://orcid.org/0000-0002-9379-953076.2679.20