Actualmente mis líneas de investigación son el microprocesado de materiales ópticos trasparentes con láseres de femtosegudo. La lista completa de mis publicaciones se pueden consultar tanto en mi perfil de Google Scholar como en mi perfil de Publons. Aquí puedes ver un resumen de las publicaciones más relevantes.
Publicaciones
Q-switching of waveguide lasers based on graphene/WS2 van der Waals heterostructure
Ziqi Li, Chen Cheng, Ningning Dong, Carolina Romero, Qingming Lu, Jun Wang
Photonics Research 5, 406 (2017) [Pdf]
Abstract:
We report on the operation of passively Q-switched waveguide lasers at 1 μm wavelength based on a graphene∕WS2 heterostructure as a saturable absorber (SA). The gain medium is a crystalline Nd:YVO4 cladding waveguide produced by femtosecond laser writing. The nanosecond waveguide laser operation at 1064 nm has been realized with the maximum average output power of 275 mW and slope efficiency of 37%. In comparison with the systems based on single WS2 or graphene SA, the lasing Q-switched by a graphene∕WS2 heterostructure SA possesses advantages of a higher pulse energy and enhanced slope efficiency, indicating the promising applications of van der Waals heterostructures for ultrafast photonic devices.
https://doi.org/10.1364/PRJ.5.000406
All-laser-micromachining of ridge waveguides in LiNbO3 crystal for mid-infrared band applications
Lingqi Li, Weijie Nie, Ziqi Li , Qingming Lu, Carolina Romero, Javier R. Vázquez de Aldana, Feng Chen
Scientific Reports 7, 7034 (2017) [Pdf]
Abstract:
The femtosecond laser micromachining of transparent optical materials ofers a powerful and feasible solution to fabricate versatile photonic components towards diverse applications. In this work, we report on a new design and fabrication of ridge waveguides in LiNbO3 crystal operating at the midinfrared (MIR) band by all-femtosecond-laser microfabrication. The ridges consist of laser-ablated sidewalls and laser-written bottom low-index cladding tracks, which are constructed for horizontal and longitudinal light confinement, respectively. The ridge waveguides are found to support good guidance at wavelength of 4 μm. By applying this configuration, Y-branch waveguiding structures (1×2 beam splitters) have been produced, which reach splitting ratios of ∼1:1 at 4μm. This work paves a simple and feasible way to construct novel ridge waveguide devices in dielectrics through all-femtosecond laser micro-processing.
DOI:10.1038/s41598-017-07587-w
Three-dimensional dielectric crystalline waveguide beam splitters in mid-infrared band by direct femtosecond laser writing
Ruiyun He, Irene Hernández-Palmero, Carolina Romero, Javier R. Vázquez de Aldana, and Feng Chen
Optics Express 22, 31293 (2014) [Pdf]
Abstract:
We report on the fabrication of three-dimensional waveguide beam splitters in a dielectric Bi4Ge3O12 (BGO) crystal by direct femtosecond laser writing. In the laser written tracks of BGO crystal, positive refractive index is induced, resulting in so-called Type I configuration waveguiding cores. The “multiscan” technique is utilized to shape cores with designed cross-sectional geometry in order to achieve guidance at mid-infrared wavelength of 4 μm. The fundamental mode guidance along both TE and TM polarizations has been obtained in the waveguide structures. With this feature, we implement beam splitters from 2D to 3D geometries, and realize 1 × 2, 1 × 3, and 1 × 4 power splitting at 4 μm.
https://doi.org/10.1364/OE.22.031293
