A SCIENTIFIC FIRST!!!
Evan Pease is measuring the even and odd order distortion signals from a superconducting microwave filter. He is using three input signals with a method being developed exclusively in the Hope College Microwave Lab called 3-tone intermodulation
distortion. This ground breaking research will help to establish the limits of superconductivity in microwave electronics and at the same time reveal new insights into the physics of high temperature superconducting materials. The graph to the right (click on it) shows the 3rd order nonlinearity, revealing a “nonlinearity catastrophe” at the superconducting transition temperature. Evan is measuring signals as small as 30 femtoWatts in this experiment.