We present a versatile off-chip coupling solution using 3D nanoprinting for both fibre-to-chip
and chip-to-chip connections. The design employs elliptical-shaped reflectors that manage mode-sizeconversion over a wide bandwidth. We experimentally demonstrate 0.8dB fibre-to-chip and 2.8dB chipto-chip coupling loss over a 140nm wavelength range.

We fabricate a hybrid integrated self-injection locked (SIL) laser, achieving a 42 Hz linewidth via a high-quality Si3N4 microring resonator, and utilize it to construct a net 400 Gb/s self-homodyne coherent transmission system, tolerating 1 km of fiber length mismatch without performing carrier phase recovery.

We’ve developed PPLN-based wavelength converters for U-band expansion, achieving 3-dB converted gain flatness and 6-dB noise figure for full U-band expansion. A converted 1.2-Tbps/ch. WDM signal is successfully transmitted over 100-km G.654.E fiber. We also demonstrate the extensibility beyond U-band up to 1719 nm.

Fully automatic phase-error calibration across a 256 dual Mach-Zehnder-interferometers-based 8×8 non-blocking silicon photonic switch fabric with polarization diversity was demonstrated. We achieve an ultra-fast and highly accurate calibration by only sampling 3.6 measurement points for one switch state, close to the theoretical limit of 3.

We leverage phase mismatch in sharp bends to enhance the performance of silicon thermo-optic phase shifters at 1550 nm. The measured insertion loss, power consumption, modulation bandwidth, and footprint are 0.14 dB, 3.4 mW/π, 10.5 kHz, and 42 μm × 42 μm, respectively.

We newly develop a free-space optics-based multi-channel variable optical attenuator (VOA) without fan-in/fan-out devices for 4-core fiber system. We experimentally demonstrate the insertion loss up to 0.56 dB and dynamic range of attenuation of more than 50 dB on four cores of the VOA.