Title :
Control of the properties of micro-structured waveguides in LiNbO3 fabricated by direct femtosecond laser inscription
Author :
Karakuzu, Huseyin ; Dubov, Mykhaylo ; Boscolo, Stefano
Author_Institution :
Aston Inst. of Photonics Technol., Aston Univ., Birmingham, UK
Abstract :
This paper reports on buried waveguides fabricated in lithium niobate (LN) by the method of direct femtosecond (fs) laser inscription. 5% MgO doped LiNbO3 was chosen as the host material because of its high quality and damage threshold, as well as relatively low cost. Direct fs inscription by astigmatically shaped beam in crystals usually produces multiple `smooth´ tracks (with reduced refractive index), which encircle the light guiding `core´, thus creating a depressed cladding WG. A high-repetition rate fs laser system was used for inscription at a depth of approximately 500 μm. Using numerical modelling, it was demonstrated that the properties of fs-written WGs can be controlled by the WG geometry. Buried, depressed-cladding WGs in LN host with circular cross-section were also demonstrated. Combining control over the WG dispersion with quasi-phase matching will allow various ultralow-pump-power, highly-efficient, nonlinear light-guiding devices - all in an integrated optics format.
Keywords :
high-speed optical techniques; integrated optics; laser materials processing; lithium compounds; magnesium compounds; micro-optics; optical control; optical fabrication; optical waveguides; LiNBO3:MgO; WG dispersion; WG geometry; buried depressed-cladding WGs; direct femtosecond laser inscription; highly-efficient devices; integrated optics format; microstructured waveguides; nonlinear light-guiding devices; quasiphase matching; ultralow-pump-power devices; Laser theory; Lithium niobate; Optical waveguides; Photonics; Refractive index; Ultrafast optics; Waveguide lasers;
Conference_Titel :
Lasers and Electro-Optics Europe (CLEO EUROPE/IQEC), 2013 Conference on and International Quantum Electronics Conference
Conference_Location :
Munich
Print_ISBN :
978-1-4799-0593-5
DOI :
10.1109/CLEOE-IQEC.2013.6800973