By scanning a fine open-ended coaxial probe above an operating microwave device, we image local electric fields generated by the device at microwave frequencies. The probe is sensitive to the electric flux normal to the face of

Nonlinearities give rise to intermodulation distortion in superconducting microwave devices and currently limit their use to low power applications. We have developed a cryogenic imaging technique to spatially resolve intermodulation distortion and used it to image an 8.2 GHz high temperature superconducting Tl2Ba2CaCu2O8 microwave resonator. The images reveal that the fundamental and intermodulation electric fields obey a fixed relation throughout the device. We note that further refinements of intermodulation theory in resonant devices may be required to fully describe the data.

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We describe the use of a cryogenic near-field scanning microwave microscope to image microwave electric fields from superconducting and normal-metal microstrip resonators. The microscope employs an open-ended coaxial probe and operates from 77 to 300 K in the 0.01-20 GHz frequency range with a spatial resolution of about 200 µm. We describe the operation of the system and present microwave images of Cu and Tl 2 Ba 2 CaCu 2 O 8 microstrip resonators, showing standing wave patterns at the fundamental and second harmonic frequencies.

We describe the near-field scanning microwave microscopy of microwave devices on a length scale much smaller than the wavelength used for imaging. Our microscope can be operated in two possible configurations, allowing a quantitative study of either material properties or local electric fields.