The PolyBoard platform enables the hybrid integration of complex and highly functional photonic integrated circuits (PICs) comprising active and passive optical functionalities. Furthermore, PolyBoard’s micro-optical bench offers structures such as U grooves, slots and vertical mirrors allowing the integration of SM fibers, GRIN lenses, NLO crystals, λ/2 and λ/4 plates, PBS/PBC, thin film filters, as well as active components like lasers, detectors and modulators.

SiN microring resonators as high-precision disposables

Photonic integrated circuits (PIC) based on SiN are becoming increasingly important not only in telecommunications, but also in point-of-care (PoC) sensor technology for diagnostics, environmental analysis, life science and food analysis.

The Fraunhofer HHI microring resonators, functionalized with capture molecules, can meet precisely these requirements. The aim of the technology development is to establish a cost-effective disposable sensor with several sensor channels, each of which is sensitized for the detection of different chemical or biological substances.

High-data rate wireless links at (sub-)THz carrier frequencies

Based on its mature InP technology, Fraunhofer HHI develops photonic components and systems for high-data rate wireless terahertz communications. These components allow for seamless integration into state-of-the-art fiber-based communication systems. Thus, complex modulation formats, such as 32QAM, 64QAM and QPSK, can be used. In a recent publication, we showed up to 160 Gbit/s at 300 GHz carrier frequency using 32QAM (Nellen et al., JLT 40(13), 2022).

Broadband spectral coverage from 100 GHz to 4.5 THz

The photonic terahertz components and systems developed by Fraunhofer HHI are well suited for test and measurement applications for 6G and beyond. In contrast to electronic mixer circuits, with a single system the photonic approach allows for broadband access to frequencies between 100 GHz and 4.5 THz. Since the specific frequency bands of future wireless communication channels are still a topic of debate, our approach helps to reduce this uncertainty by providing access to a broad spectral range.

Components for 1Tb/s Transmission and Microwave Photonics

Fraunhofer HHI provides single and balanced photodetector modules with a bandwidth up to 145 GHz operating from the O- to the L-band. The intended application for the modules is test and measurement. For the application of microwave photonics dedicated high-power photodetector modules are presented.

High-Speed Electro-Optic Modulators and more

High-speed electro-optic phase shifter, fiber-spot size converter, thermo-optic phase-shifter, on-chip resistor, and other building blocks on thin-film lithium-niobate for Mach-Zehnder modulator based PICs.

4.9 W 1550 nm Broad Area Laser

Fraunhofer HHI develops 1550 nm InGaAsP MQW based broad area single emitters with 100 µm stripe width showing 4.9 W CW output power at 20°C operation temperature and a maximum wall plug efficiency of 40%. A low loss large optical cavity design allows for a narrow optical far-field of 25° x 15° FHWM. Optional, a (DBR) wavelength stabilization can be realized (Photonic West 2024 Paper 12867-5).

We show neuromorphic computing using reservoir architecture for use-cases such as smart monitoring of state-of-the-art optical modulation formats. Our 4mm-by-7mm SOI-based photonic integrated circuit can predict modulation formats after 100 km transmission with an accuracy of more than 97%.