New Ca10Li(VO4)7 laser host: growth and properties
|Alexey N. Shekhovtsov 1, Myron B. Kosmyna 1, Viacheslav M. Puzikov 1, Boris N. Nazarenko 1, Wojciech Paszkowicz 2, Akram Behrooz 2, Przemysław Romanowski 2, Anatoliy S. Yasukevich 3, Nikolay V. Kuleshov 3, Maxim P. Demesh 3, Wojciech Wierzchowski 4, Krzysztof Wieteska 5, Carsten Paulmann 6|
1. Institute for Single Crystals NAS of Ukraine (ISC), 60 Lenin Ave., Kharkov 61001, Ukraine
The unique combination of physical-chemical properties of the vanadate crystals makes them promising hosts for active elements of diode-pumped high-efficient CW, Q-switched and mode-locked lasers. The particular advantages of these materials are high thermal conductivity, chemical stability, low lasing threshold, and high lasing efficiency. The stimulated emission cross section of Nd3+ is much larger than that of YAG:Nd crystal.
Disordered calcium vanadates with trigonal structure are attractive materials for non linear optics because of efficient second harmonic generation . Moreover disordered calcium vanadates are promising hosts for diode pumping lasers. The Ca10Li(VO4)7 vanadate was chosen for investigations of crystal growth and laser application abilities.
A solid state synthesis was carried out to produce Ca10Li(VO4)7 compound. For the growth process, an automatic “Analog” puller equipped with a weight control system was used. Cylindrical crystals of diameter up to 25 mm and length up to 50 mm were grown from a  oriented seed by the Czochralski technique. The pure crystals were of yellow colour, whereas Nd doped crystals were lilac.
The crystal structure of Ca10Li(VO4)7 single crystal was determined by the powder diffraction method. Defect structure of crystal was studied with the use of both, high-resolution diffraction using a laboratory instrument and X-ray topographic techniques employing synchrotron radiation at the Hasylab laboratory (Hamburg).Polarized absorption and luminescence spectra of Nd doped Ca10Li(VO4)7 crystal were investigated in details. Spectral and temporal characteristics of Nd3+ luminescence associated with 4F3/2→4I9/2, 4I11/2 and 4I13/2 transitions were studied. At Nd3+ doping the laser oscillation was obtained under flash lamp pumping. The slope efficiency of 0.87% was achieved in the free-running mode. The ways of lasing efficiency increasing are discussed.
Presentation: Oral at 17th International Conference on Crystal Growth and Epitaxy - ICCGE-17, Topical Session 6, by Alexey N. Shekhovtsov
See On-line Journal of 17th International Conference on Crystal Growth and Epitaxy - ICCGE-17
Submitted: 2013-03-29 14:21 Revised: 2013-03-29 14:21