Title Trijų ir keturių bangų parametrinių sąveikų taikymas ultratrumpųjų impulsų generacijai ultravioletiniame, artimajame ir viduriniajame infraraudonajame spektro ruože /
Translation of Title Three and four wave parametric interactions for ultrashort pulse generation in the ultraviolet, near and mid-infrared spectral range.
Authors Darginavičius, Julius
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Pages 48
Keywords [eng] Nonlinear optics ; optical parametric amplification ; three wave mixing ; four wave mixing.
Abstract [eng] In this thesis we investigated and developed three- and four-wave interaction-based frequency conversion methods for ultrashort pulse generation in the ultraviolet (UV), near and mid-infrared (IR) spectral ranges. In particular, efficient generation of Nd:glass laser harmonics was demonstrated experimentally, through noncollinear four-wave difference-frequency mixing in isotropic media. Also, broadband optical parametric amplification in the UV was investigated theoretically and achieved experimentally. The results suggest, that pulses as short as 10 fs could be amplified. We have also developed two methods based on three- and four-wave mixing, that extend the tuning range of a commercial Ti:sapphire laser-NOPA system in the IR. The first method relies on four wave frequency down-conversion, and can achieve up to 20 μJ, sub-30-fs pulses tunable in the 1−1.5 μm range. The second method considers frequency conversion, based on difference frequency generation and optical parametric amplification in BBO crystals. The presented setup delivers two optical-cycle, carrier-envelope phase (CEP)-stable pulses at 2 μm. And finally, we demonstrated supercontinuum generation by filamentation of 20 fs pulses at 2 μm in wide-bandgap solids in the regime of anomalous group velocity dispersion. We also proposed the practical use of intrinsic third harmonic generation, for the CEP stability measurements.
Type Summaries of doctoral thesis
Language Lithuanian
Publication date 2013