Centimetre-scale micro-transfer printing to enable heterogeneous integration of thin film lithium niobate with silicon photonics
Margot Niels, Tom Vanackere, Tom Vandekerckhove, Stijn Poelman, Tom Reep, Günther Roelkens, Maximilien Billet, Bart Kuyken
Abstract
The integrated photonics CMOS-compatible silicon nitride (SiN) platform is praised for its low propagation loss but is limited by its lack of active functionalities such as a strong Pockels coefficient and intrinsic χ (2) nonlinearity. In this paper, we demonstrate the integration of centimetre-long thin-film lithium niobate (TFLN) devices on a SiN platform using the micro-transfer printing (µTP) method. At a wavelength of 1550 nm, propagation losses of approximately 0.9 dB/cm and transition losses of 1.8 dB per facet were measured. Furthermore, the TFLN was integrated into an imbalanced push-pull Mach-Zehnder modulator, achieving a V π of 3.2 V. The electro-optic nature of the observed modulation is confirmed by measuring the device up to 35 GHz, showing that the printing does not affect the high-speed LN properties.