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Vorträge und Posterpräsentationen (mit Tagungsband-Eintrag):

F. Bammer, R. Petkovsek, J. Mozina, D. Schuöcker:
"Q-switching a fiber laser with a dual mode single crystal photo-elastic modulator";
Vortrag: Photonics Europe 2008 (SPIE), Straßburg; 07.04.2008 - 10.04.2008; in: "Solid State Lasers and Amplifiers III", T. Graf, J. Terry, H. Jelinkova (Hrg.); SPIE, 6998 (2008), ISSN: 0277-786x; S. 1 - 8.



Kurzfassung deutsch:
We present a new optical device for pulse picking and Q-switching based on a LiTaO3-crystal together with polarizers.
LiTaO3 is piezoelectric, hence when a harmonic voltage course with a proper frequency is applied to the crystal it will
start to oscillate resonantly in a mechanical eigenmode. Due to photo-elasticity an artificial modulated birefringent is
induced by this oscillation such that the polarization of trough-going light is modulated. Together with polarizers the
transmission of the whole setup can oscillate between 0 and 100%. The applied voltage amplitude is usually in the order
of below 10 V. With a special choice of the crystal dimensions it is possible that the first shear eigenmode has exactly
three times the frequency of the first longitudinal eigenmode. Both modes have qualitatively the same influence on
polarization, such that with a proper superposition of these two modes a short opening time of the setup can be achieved,
which can be used to enforce pulsed laser operation. The latter was realized with a small end pumped fibre laser. A pulse
sequence with 127 kHz and a ratio of peak power to average power of ~30 was achieved.

Kurzfassung englisch:
We present a new optical device for pulse picking and Q-switching based on a LiTaO3-crystal together with polarizers.
LiTaO3 is piezoelectric, hence when a harmonic voltage course with a proper frequency is applied to the crystal it will
start to oscillate resonantly in a mechanical eigenmode. Due to photo-elasticity an artificial modulated birefringent is
induced by this oscillation such that the polarization of trough-going light is modulated. Together with polarizers the
transmission of the whole setup can oscillate between 0 and 100%. The applied voltage amplitude is usually in the order
of below 10 V. With a special choice of the crystal dimensions it is possible that the first shear eigenmode has exactly
three times the frequency of the first longitudinal eigenmode. Both modes have qualitatively the same influence on
polarization, such that with a proper superposition of these two modes a short opening time of the setup can be achieved,
which can be used to enforce pulsed laser operation. The latter was realized with a small end pumped fibre laser. A pulse
sequence with 127 kHz and a ratio of peak power to average power of ~30 was achieved.

Schlagworte:
photo-elastic modulator, LiTaO3, Q-switching, fiber laser

Erstellt aus der Publikationsdatenbank der Technischen Universität Wien.