To reduce the ever-increasing energy consumption in datacenters, one of the effective approaches is to increase the ambient temperature, thus lowering the energy consumed in the cooling systems. However, this entails more stringent requirements for the reliability and durability of the optoelectronic components. Herein, we fabricate and demonstrate silicon-polymer hybrid modulators which support ultra-fast single-lane data rates up to 200 gigabits per second, and meanwhile feature excellent reliability with an exceptional signal fidelity retained at extremely-high ambient temperatures up to 110 °C and even after long-term exposure to high temperatures. This is achieved by taking advantage of the high electro-optic (EO) activities (in-devicen³r₃₃ = 1021 pm V⁻¹), low dielectric constant, low propagation loss (α, 0.22 dB mm⁻¹), and ultra-high glass transition temperature (T_g, 172 °C) of the developed side-chain EO polymers. The presented modulator simultaneously fulfils the requirements of bandwidth, EO efficiency, and thermal stability for EO modulators. It could provide ultra-fast and reliable interconnects for energy-hungry and harsh-environment applications such as datacentres, 5G/B5G, autonomous driving, and aviation systems, effectively addressing the energy consumption issue for the next-generation optical communication.

All-optical wavelength conversion (AOWC) plays an important role in the future transparent optical networks, in order to enhance the re-configurability and non-blocking capacity. On the other hand, high-order quadrature amplitude modulations (QAMs) have been extensively studied for achieving the high-speed and high-spectral-efficiency optical transmission. Since high-order QAMs are more sensitive to phase and amplitude noise, to implement an AOWC sub-system suitable for high-order QAM signals with minimized power penalty, it is important to optimize the operation conditions in order to avoid extra nonlinear distortions co-existed in the AOWC process. Our experimental results show that, constellation monitoring provides a more intuitive and accurate approach to monitor the converted high-order QAM signals, especially in presence of nonlinear phase noise such as self-phase modulation (SPM). We experimentally demonstrate an AOWC of 64QAM signal through four-wave mixing (FWM) in highly-nonlinear (HNLF). The performance of the AOWC is optimized through the constellation monitoring of the converted signal, achieving a negligible power penalty (<0.3dB at BER of 10⁻³) for 60-Gbps 64QAM after conversion.

An optical format conversion scheme of multilevel phase-shift keying (M-ary PSK) signals using the four-wave mixing based optical phase erasure is discussed in this paper. The conversion from differential quadrature phase-shift keying (DQPSK) to differential phase shift keying at 10 and 160 Gbaud, and the conversion from differential eight-ary phase-shift keying to DQPSK at 40 Gbaud have been experimentally demonstrated. The proposed scheme could be used as a phase erasure, in which a redundant tributary of the M-ary PSK signal is removed, or as an “updater” where the unwanted phase pattern is replaced with the new pattern.

We propose a novel 16-quadrature amplitude modulation (QAM) transmitter based on two cascaded IQ modulators driven by four separate binary electrical signals. The proposed 16-QAM transmitter features scalable configuration and stable performance with simple bias-control. Generation of 16-QAM signals at 40 Gbaud is experimentally demonstrated for the first time and visualized with a high speed constellation analyzer. The proposed modulator is also compared to two other schemes. We investigate the modulator bandwidth requirements and tolerance to accumulated chromatic dispersion through numerical simulations, and the minimum theoretical insertion attenuation is calculated analytically.

The gap between the performance of optoelectronic components and the demands of fiber-optic communications has narrowed significantly in recent decades. Yet, the expansion of data communications traffic remains substantial, with fiber-link speeds increases anticipated in the near future. Here, we demonstrate an ultra-high-speed electro-optic waveguide modulator constructed using a thin film of lanthanum-modified lead zirconate titanate with a ferroelectric phase exhibiting a strong Pockels effect. The modulator has a wide optical window; thus, the modulation was demonstrated for 1550 and 1310 nm wavelengths. This device showed electro-optical intensity signaling with line rates of 172 Gbit s⁻¹, in conjunction with on–off keying modulation; this performance could be increased to 304 Gbit s⁻¹ using four-level pulse modulation. The signaling performance of this modulator was found to be robust, with stable performance at temperatures as high as 100 °C. This technology is expected to have applications in a wide range of classical optoelectronic devices and in quantum science and technology.