At Micro Harmonics we are developing a line of isolators designed for optimal performance at cryogenic temperatures. The ferrite is biased in magnetic saturation for minimal insertion loss and the length of the ferrite rod is optimized to achieve the desired rotation at cryogenic temperatures.
Sophisticated models are constructed to simulate the thermal stress levels throughout the isolator as it is cooled. Materials are chosen that reduce thermal stress. Reliability is verified through repeated thermal cycling in a liquid nitrogen bath. Our isolators are built to withstand the rigors of repeated cryogenic cycling.