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Laser Optics & Photonics and Atomic & Plasma Science 2018
J u l y 1 6 - 1 7 , 2 0 1 8
P r a g u e , C z e c h R e p u b l i c
Page 93
American Journal of Computer Science and Information Technology
ISSN: 2349-3917
E u r o S c i C o n J o i n t E v e n t o n
Laser Optics & Photonics and
Atomic & Plasma Science
F
emtosecond lasers have become a powerful tool for three-dimensional precision micromachining of dielectrics. One of its
promising applications is space-selective laser-induced crystallization of glasses providing growth of continuous crystalline
architectures with functional properties such as second-order optical nonlinearity. Though laser-induced precipitation of
different crystalline phases was demonstrated in a wide set of glasses, writing single-crystal tracks which could operate as
channel waveguides was a challenge which required optimization of laser treatment parameters and beam profiling. Such
crystalline channel waveguides consisting of ferroelectric stillwellite LaBGeO
5
phase have been recently obtained in lanthanum
borogermanate glass. In particular, we reported laser writing of oriented LaBGeO
5
tracks with improved homogeneity providing
waveguide effect by applying the femtosecond beam with elliptical waist cross-section and demonstrated second harmonic
generation in this waveguide. In the present study, we revealed the possibility and investigated conditions of laser direct writing
of oriented LaBGeO5 crystal tracks at various pulse duration from 300 fs - 5 ps and various pulse repetition rates from 25 kHz to
500 kHz. It is shown that there is a constant minimal value of peak pulse intensity about 1,6 10
12
W/cm
2
in the pulse repetition
rate range of 100-500 kHz, while at lower repetition rates this value rapidly grows with repetition rate decrease. We also suggest
a method of fast laser-induced growth of a seed microcrystal which is necessary as a starting point for writing a crystalline track
and is formed in glass by the stationary beam. Exposure of glass to the beam with gradually increasing pulse energy is shown
to greatly reduce and stabilize time required to grow a seed crystal as compared to the beam with constant pulse energy. The
obtained data will be useful for further improvement and feasibility of crystal-in-glass waveguides writing method.
sergey_lot@mail.ru slotarev@muctr.ruFemtosecond laser direct writing of crystal-in-
glass LaBGeO5 waveguides
Sergey V Lotarev, Alexey S Lipatiev, Tatiana O Lipateva,
Vladimir N Sigaev
Mendeleev University of Chemical Technology of Russia, Russia
Am J Compt Sci Inform Technol 2018, Volume 6
DOI: 10.21767/2349-3917-C1-003