Y.C. Huang

Observation of thermal-induced optical guiding and bistability in a mid-IR continuous-wave, singly resonant optical parametric oscillator

We report the observation of thermal-induced optical guiding and bistability in a mid-IR cw, singly resonant optical parametric oscillator (SRO) at ~3.2 μm. The SRO employs a MgO:PPLN crystal as the gain medium and a 1-nm-linewidth Yb-fiber laser at 1.064 μm as the pump source. As soon as the pump power reaches the thermal guiding threshold at 16.5 W, the SRO shows a step increase in the parametric efficiency by a factor of 2.5. At 25 W pump power, the SRO generated 5.3 and 1.2 W at 1.58 and 3.23 μm, respectively, with single-longitudinal-mode performance for the 3.23 μm radiation.

Monolithic quasi-phase-matched nonlinear crystal for simultaneous laser Q switching and parametric oscillation in a Nd:YVO 4 laser

We report the performance of a periodically poled lithium niobate (PPLN) crystal inside a diode-pumped Nd:YVO4 laser for simultaneous laser Q switching and optical parametric oscillation. The monolithic PPLN crystal consists of two sections, a 1-cm-long 14-microm-period electrode-coated section and a 4-cm-long 30-microm-period section, functioning as a low-voltage Pockels cell and a quasi-phase-matched parametric gain medium, respectively. At a 150-V Q-switching voltage and a 6-kHz switching rate, we measured 25-microJ pulse energy and 4-kW peak power at 1.55 microm with 9-W absorbed diode power.

Even-order Spectral Phase Retrieval by Modified Interferometric Field Autocorrelation Trace

We proposed analytic retrieval of all even-order spectral phase components by measuring modified interferometric field autocorrelation trace using thick nonlinear crystals. This new scheme is attractive in measuring ultraweak ultrashort optical pulses.

Complete spectral phase retrieval by modified interferometric field autocorrelation traces

We propose analytic retrieval of complete spectral phase profile by measuring two modified interferometric field autocorrelation traces using thick nonlinear crystals with slightly different central phase-matching wavelengths.

Active Narrowband Multiple Wavelength Filters and Frequency Doublers in Aperiodically Poled Lithium Niobates

We report the first experimental demonstration of active narrowband multiple wavelength filters in aperiodically poled lithium niobate (APLN) crystals. Simultaneous transmission of >90% (~100% in design) of 8 telecom wavelengths was achieved in this device.

Waveguide-enhanced THz parametric generation and oscillation in thin lithium niobate wafers

We observed 2-time efficiency increase in THz parametric generation when reducing the thickness of a lithium-niobate waveguide from 1 to 0.5 mm. Efficient THz emitted from such a waveguide OPO with an intracavity grazing-incidence grating.

Distributed feedback optical parametric oscillation by using a two-photon photorefractive grating in periodically-poled lithium niobate

We successfully demonstrated a distributed-feedback optical parametric oscillation (DFB OPO) by writing two-photon photorefractive gratings in a periodically poled lithium niobate crystal. Evidence of OPO was observed from the spectral narrowing at the 619.3 nm.

Actively Q-switched Nd:YVO/sub 4/ laser using a low-voltage electro-optic PPLN crystals as the laser Q-switch

We present a < 100 V switching-voltage electro-optically Q-switched Nd:YVO/sub 4/ laser by using a periodically poled lithium niobate (PPLN) polarization rotator as the laser Q-switch. 9-ns pulse-width and 0.85-kW 1064 nm laser pulses were obtained with this system.

Distributed feedback optical parametric oscillator

Summary form only given. We have demonstrated the DFB periodically poled LiNbO/sub 3/ (PPLN) optical parametric oscillator (OPO) by writing a photorefractive grating in a PPLN. The detail properties are under investigating now. The DFB PPLN OPO may lead to novel applications in gas sensing and fiber communications.