RT Journal Article T1 Waveguide tapers fabrication by femtosecond laser induced element redistribution in glass A1 Macías Montero, Manuel A1 Dias, Antonio A1 Sotillo Buzarra, Belén A1 Moreno Zárate, Pedro A1 Ariza, Rocío A1 Fernández Sánchez, Paloma A1 Solís, Javier AB Here in we present the fabrication and performance of waveguide tapers produced by femtosecond laser induced element redistribution in modified phosphate glasses. More particularly, it is demonstrated that by controlling the scan velocity during the writing process it is possible to adequately tune both the size of the modified area and the refractive index contrast to produce waveguides that can cope with mode field diameters in the range of 7 mu m. In addition, we fabricated tapered structures through the induction of an acceleration in the laser scanning velocity, resulting in a device that can efficiently convert a wide range of mode fields. The fine control achieved over the index contrast in the range of 10^(-3) and 10^(-2) would allow the production of a wide variety of tapers that could potentially be used to couple numerous photonic devices. PB Institute of Electrical and Electronics (IEEE) SN 0733-8724 YR 2020 FD 2020-12-01 LK https://hdl.handle.net/20.500.14352/7603 UL https://hdl.handle.net/20.500.14352/7603 LA eng NO © 2020 IEEEM.M. acknowledges the postdoctoral Juan de la CiervaIncorporación grant (IJCI-2017-33317)) of the Spanish Ministry of Research and Innovation. B.S. acknowledges the postdoctoral grant from the “Atracción de Talento” Program funded by the Comunidad de Madrid (2017-T2/IND-5465). P.M.-Z. acknowledges the postdoctoral scholarship #235346 awarded by the National Council of Science and Technology from Mexico (CONACYT). NO Comunidad de Madrid NO Juan de la Cierva (MICINN) DS Docta Complutense RD 8 abr 2025