The world’s first WR-2.8 Faraday rotation isolator, Model FR28. The FR28 is designed to cover the entire band from 260-400 GHz. The challenges in fabricating and aligning the constituent parts have been monumental, but we managed to assemble the first batch of prototypes in May 2021. We are excited to bring this unique component to the marketplace.

The global demand for the FR28 has been high, and we are working hard to produce this component in the necessary quantities. If you have an interest in purchasing one of these isolators, please contact us soon so that we can plan accordingly.

The FR28 specification sheet showing measured data is shown below. The FR28 exhibits state-of-the-art performance in terms of low-insertion loss, broad-bandwidth, and low port reflections. Since there is nothing to compare it to, the FR28 defines the state-of-the-art.

Internal access to all eight of the flange screws is provided so that you do not have to use lossy and expensive intervening waveguides in your system. The initial production runs did not have diamond heatsinks. However, the FR28 now has a diamond heatsink to allow for higher power handling.

The picture below shows the initial production of the core assembly of the FR28 isolator. The core comprises a black ferrite rod and two white alumina ceramic cones. The total length is about 4 mm. Each cone has a resistive layer bisecting the central axis. Fabricating the cones at this size has been a major challenge. Since we bias our isolators in magnetic saturation, the ferrite length has to be tightly controlled. The resistive layers have to be aligned at 45° with respect to each other and then precisely aligned in the waveguide block. And the core needs to be assembled with great care so as not to break the diamond disc heatsink (not shown in picture).

Click here for a full listing of waveguide isolators and specs.