A5018576221- Photorefractive and Nonlinear Optics
- Photonic and Optical Devices
- Advanced Fiber Laser Technologies
- Solid State Laser Technologies
- Ferroelectric and Piezoelectric Materials
- Optical Polarization and Ellipsometry
- Photonic Crystals and Applications
- Optical Systems and Laser Technology
- Optical Coherence Tomography Applications
- Terahertz technology and applications
- Advanced Optical Sensing Technologies
- Optical Coatings and Gratings
Gwangju Institute of Science and Technology
2006-2024
National Institute for Materials Science
2005
Spectrally broad frequency comb generation over 510–555 nm range was reported on chirped quasi-phase-matching (QPM) χ(2) nonlinear photonic crystals of 12 mm length with periodicity stepwise increased from 5.9 μm to 7.1 μm. When pumped nanosecond infrared (IR) derived a QPM optical parametric oscillator (OPO) and spanned 1040 1090 wavelength range, the 520 545 up-converted green spectra were shown consist contributions (a) second-harmonic among signal or idler modes, (b) sum-frequency (SFG)...
We demonstrate one-dimensional beam steering in a liquid crystal on silicon (LCOS) device with large birefringence (Δ <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</i> = 0.2028 at 1550 nm) of the (LC) mixture. The experimental analysis optical angles different LCOS grating periods is reported. A maximum angle ±15.6° measured for fine pitch 3.6 μm 1 <sup xmlns:xlink="http://www.w3.org/1999/xlink"><i>st</i></sup> -order diffraction...
We demonstrate 3 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> -order QPM SHG in periodically-twinned quartz under tight focusing condition of a Nd:YAG laser. Owing to large temperature bandwidth, stable and efficient green light 31 mW was obtained without control
Parallel excitation of optical parametric oscillations was observed on PPLT dispersed with tri-QPM structures in the transverse direction to a nano-second pump beam. It led simultaneous IR generation from 1000 1150nm slope efficiency > 30%. When nonlinearly-chirped subject such pump, it exhibits broad green 500 560nm single pass ∼10%. This due spectral coverage QPM-SHG and SFG chirp structures.
Up to 2.8 nm of filtering bandwidth was achieved with a simple temperature-gradient-control technique in 78-mm-long Ti-diffused periodically poled LiNbO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> (Ti:PPLN) waveguide, which has 0.2-nm wavelength at an uniform temperature.
We demonstrated tunable and narrow-band terahertz generation around l~3 THz via difference frequency (DFG) using femtosecond (fs) pulses in a periodically poled lithium niobate (PPLN) crystal stoichiometric tantalate (PPSLT) crystal. Two different types of radiation, forward backward, could be generated the quasi-phase matching (QPM) structures by DFG process. A broadband fs optical pulse contributes to process, which occurs between two components set an ultrashort within range at QPM...
Using periodically-poled stoichiometric lithium tantalate, peak power of 21.6 MW/cm/sup 2/ at 532 nm was achieved. A small temperature adjustment required with 4.4 W SH room due to its high thermal conductivity.
Periodical poling process in stoichiometric lithium tantalate is described. Appropriate parameters allow high uniformity of domain structures along the length and depth, leading to efficiency extended effective aperture
Computational study of nanosecond pulse laser radiation in periodically poled LiNbO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> crystals reveals the complex spatio-temporal evolution 1.064 μm fundamental harmonic and second energy fields with associated temperature fields, leading to thermal dephasing inhibition generation.