• Korean Journal of Optics and Photonics
• /
• v.17 no.3
• /
• pp.262-267
• /
• 2006

We proposed a PPLN fabrication setup that measures the voltage and current applied to $LiNbO_3$ in real time during application of a DC electric field. Because the duration for transferring a sufficient electron charge to $LiNbO_3$ increases, we are able to control the electron charge flow transferred to $LiNbO_3$ efficiently. We divided the domain inversion process of PPLN into 5 states: Nucleation (state 1), Spread of the domain inversion region under the electrode(state 2), Accumulation of the electron charge at the insulator/$LiNbO_3$ interface(state 3), Domain inversion under the insulator layer after breakdown(state 4), and Lowering the electric field applied to $LiNbO_3$ (state 5). We have found that the Threshold Point is essential for the domain inversion and that the domain inversion process must be stopped within state 3 for the optimum PPLN. Using these results, we could fabricate a stable and reproducible PPLN efficiently.

• Korean Journal of Optics and Photonics
• /
• v.19 no.6
• /
• pp.408-415
• /
• 2008

The characteristics of a ferroelectric-domain inverted grating fabricated by applying a high-voltage pulse at room temperature in Ti-diffused channel waveguides in z-cut $LiNbO_3$ (Ti:PPLN) were examined for channel waveguide quasi phase-matched secondharmonic generation devices. The fabrication conditions of uniform periodic domain-inversion were examined. Ti:PPLN with period ${\Lambda}=16.6{\mu}m$ for SHG were fabricated and the performances were measured. A normalized SHG efficiency as high as 473 (%/W) was obtained with 49 mm interaction length.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.9 no.4
• /
• pp.161-168
• /
• 2009

We demonstrated $\check{S}$olc-type wavelength filters in periodically poled Ti-diffused lithium-niobate channel optical waveguide (Ti:PPLN). A $\check{S}$olc-type transmission spectrum based on the polarization-mode conversion was observed experimentally in PPLN with period 16.6${\mu}m$. A reasonable explanation of such a phenomenon was presented. A polarization-mode converted transmission peak was observed at wavelength 1272.49nm. The FWHM and sidelobe of spectrum are about 0.23nm and 7 dB, respectively.

• Proceedings of the Optical Society of Korea Conference
• /
• 2008.07a
• /
• pp.143-144
• /
• 2008

• Korean Journal of Optics and Photonics
• /
• v.16 no.4
• /
• pp.366-375
• /
• 2005

A fabrication process of periodic electric field assisted poling of Ti-diffused channel waveguides in LiNbO3 (Ti:PPLN) has been developed and improved using a periodic 180o phase inversion along the z-axis. The zig for poling inversion and the Labview program of charge control have been devised. Pulse high voltage and duty cycle were adjusted based on the estimated charge required for poling inversion. Monitoring the change of leakage current under applied voltage less than the coercive voltage also minimized a breakdown.

• Journal of the Optical Society of Korea
• /
• v.18 no.6
• /
• pp.762-765
• /
• 2014

We fabricated a periodically poled lithium niobate (PPLN) by direct laser-writing of a quasi-phase-matching (QPM) structure in photolithographic process. Because we do not need to prepare a photomask by electron-beam writing, the "maskless" process shortens the fabrication time and significantly reduces the cost. We evaluated the poling quality of the direct laser-written PPLN by measuring the diffraction noise from the surface relief pattern of the fabricated QPM grating and comparing the results to those from a conventional PPLN made with a photomask. The quality of the PPLN fabricated by direct laser-writing was shown to be equivalent to that fabricated by the conventional method.

• Proceedings of the Optical Society of Korea Conference
• /
• 2005.07a
• /
• pp.220-221
• /
• 2005

• Proceedings of the Optical Society of Korea Conference
• /
• 2004.02a
• /
• pp.274-275
• /
• 2004

• Proceedings of the Optical Society of Korea Conference
• /
• 2009.10a
• /
• pp.26-27
• /
• 2009

• Proceedings of the Optical Society of Korea Conference
• /
• 2008.07a
• /
• pp.229-230
• /
• 2008