Optical waveguides performance and spectroscopy made in Cr: LiSAF by femtosecond micromachining

BIASETTI, DEMIAN A.; TEJERINA, MATÍAS; TORCHIA, GUSTAVO A.

La Habana

Congreso; International Conference of Optics, Photonics and Photosciences; 2014

Universidad Nacional de La Habana

Optical waveguides femtosecond micromachining has become an extended fabrication method due to the reduction on fabrication stages number and also the wide range of processing materials. [1]. In this way, exploring new active optical materials result in an interesting goal to waveguides fabrication offering technological potential like new tunable lasers creation and other applications. In this work we have fabricated type II [2] waveguides in a 1% doped Cr:LiSAF crystal sample by femtosecond laser micromachining with energies from 1 to 3 μJ per pulse and with scanning speed from 15 to 45 μm/sec, and also characterize the optical wave guiding performance using and ?end-fire? coupling system. We found good wave guiding qualities for both TM and TE polarization modes as well as acceptable losses according to expecting values in view of technological applications. By other side we proposed measurement of luminescence spectrum of Cr+3 ion and its corresponding lifetime for 4T2 --> 4A2 transition for bulk as well for waveguide trapped ions in order to find possible spectral shift for active ion luminescence due to residual stress in focal volume zone [3]. For the used parameters range of micromachining ions the waveguides keep spectroscopically unchanged compared with those in bulk. However experimental waveguide cross section mapping of high resolution micro-spectroscopy is fundamental to understand structural modification induced near focal volume of femtosecond laser pulses and its effects on waveguides supported polarization. Finally, we proposed a further investigation using confocal micro-luminiscence complemented with an elasto-optic model.