PolyBoard- and silicon-nitride-platforms

The Fraunhofer HHI platforms enable the hybrid integration of active and passive optical components in photonic integrated circuits (PICs) in the visible and infrared wavelength range. The micro-optical-bench of the PolyBoard platform facilitates PICs with spectral filters, optical isolators and circulators, as well as nonlinear crystals for applications in quantum optics, among others. The silicon-nitride-platform features highly integrated optical gratings, switches and ring resonators for communications, sensing and medical technology.

InGaAs based SWIR Photodetectors 
 
We provide InGaAs-based photodiodes with high sensitivity at NIR and SWIR wavelengths. Quantum efficiencies are up to 99%, and dark current density is 10 nA/cm² at room temperature. In order to cover the complete SWIR range up to 2500 nm, extended InGaAs based photodiodes are available as well. Customized segmented or array devices can be provided on demand.

A compact RF PIC assembly for fast and convenient prototype development up to 40 GHz

RFconnect, Fraunhofer HHI’s new fiber coupled RF PIC assembly, states a compatible expansion of the already established DC multisource PIConnect. The thermally controllable assembly with 8 RF & optical ports and 42 DC ports facilitates the connection of RF measurement equipment.

Terahertz modules for sensing and wireless communications
 
We present the newest generation of fiber-coupled terahertz modules for application in spectroscopy and non-destructive testing as well as 6G communications.

Our newly developed semiconductor layers make it possible to raise the terahertz output power to 970 µW and thus increase the dynamic range. This can lead, for example, to a significant improvement in the reliability of thickness determination of very thin layers.

With 6G wireless communications another new and rapidly growing field of application emerges. Using optoelectronic conversion, our terahertz modules allow complex optical modulation formats (e.g. quadrature amplitude modulation) to be transferred to wireless communication channels at carrier frequencies from 100 GHz to >500 GHz. This was used to demonstrate a data rate of up to 160 Gbit/s in the 300 GHz band.

Broadband spectral coverage from 100 GHz to 4.5 THz

The photonic continuous-wave terahertz 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.

Highest optical Output Power from a single Emitter

Fraunhofer HHIs newest generation of high-power Laser dioides provide up to 4.9 Watt in cw-operation around 1550 nm from a single 100µm emitter. The devices can be used in a wide range of applications in industry, medical and defense.