Nonlinear Optics

Our research in nonlinear optics focuses on light–matter interactions that enable frequency conversion processes such as second-harmonic generation (SHG), sum-frequency generation (SFG), supercontinuum generation (SCG), and optical parametric amplification (OPA).

Recent Work

In our latest efforts, we have developed periodic poling of thin-film lithium niobate (TFLN) for highly efficient second-order nonlinear processes. By integrating a periodically poled waveguide with a broadband electro-optic modulator, we realized a high-bandwidth, high-extinction-ratio modulator operating in the visible wavelength range — with direct applications in trapped-ion experiments.

In another recent advance, we demonstrated a compact, low-threshold optical parametric oscillator (OPO) based on a periodically poled waveguide combined with monolithic Bragg reflectors. The device incorporates a directional coupler for in- and out-coupling, enabling a remarkably small footprint. This simple and fully integrated design allows multiple OPOs to be implemented on a single chip, paving the way for Ising machines and optical computing. Furthermore, local thermal tuning of the waveguide provides precise control over the output wavelength.