Wideband MgB2 Hot-Electron Bolometer Mixers: IF Impedance Characterisation and Modeling
نویسندگان
چکیده
In this paper we present a method for low signal S11 parameter vector measurements of a cryogenic device in the microwave frequency range. In particularly, the intermediate frequency (IF) impedance of MgB2 Hot-electron Bolometer (HEB) mixers was investigated over a frequency range of 100 MHz to 10 GHz. A new cryogenic calibration technique which employs the HEB as a calibration kit and two consecutive thermal cycles was developed for this purpose. The real part of measured IF impedance showed a strong correlation with the differential resistance (dV/dI) obtained from the dc I-V curves while the imaginary part was capacitive for almost the entire frequency range.
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