Electro-optically spectrum switchable, multiwavelength optical parametric oscillators based on aperiodically poled lithium niobate

Abstract

We report the first fast switchable multiwavelength optical parametric oscillator based on aperiodic optical superlattice technology. The constructed aperiodically poled lithium niobate (APPLN) integrates the functionalities of two quasi-phase-matching devices on a chip to work simultaneously as an electro-optic (EO) switchable notch-like filter and a multiline optical parametric downconverter. When such an APPLN is built in a 1064-nm-pumped optical resonator system, we achieve the oscillation of dual signals at 1540 and 1550 nm, for a single signal at 1540 nm, and a single signal at 1550 nm in the system when the 3-cm-long APPLN is driven by 0 V, 354 V, and 805 V, respectively. The switching among the three signal spectra is operationally simple and electro-optically fast. The electro-optically switched signals also feature enhanced power spectral density due to the unique EO gain-spectrum filtering mechanism employed in this work.

Ultra-broadband and low-loss edge coupler for highly efficient second harmonic generation in thin-film lithium niobate

“…Lithium niobate is an ideal material for nonlinear photonics due to its exceptional nonlinear-optic properties, wide transparency range, and ferroelectric properties. 1,2 Periodically poled lithium niobate (PPLN) waveguides, where the periodic domain inversion allows for a quasi-phase-matched (QPM) second-order nonlinear [χ ð2Þ ] process, have been widely used in wavelength conversion, 3,4 optical parametric oscillation, [5][6][7][8] photon pair generation, [9][10][11][12] and supercontinuum generation. [13][14][15] As the strength of the nonlinear interaction is proportional to the optical intensity, the employment of high-contrast waveguides with strong optical confinement can greatly improve nonlinear optical efficiency.…”