| Abstract: |
We describe measurements of the performance of ampli ers in the 4{8 GHz range using DCSQUIDs in a lumped element con guration. We have used quarter wave resonators as input transformers and multipole output transformers to couple microwave power into and out of the DC SQUIDs. By choosing appropriate values for coupling capacitors, resonator lengths and output component values, we have demonstrated useful gains in several frequency ranges, with different bandwidths, showing over 30 GHz of gain-bandwidth product. In this work, we describe our design for the 4{8 GHz range and present data demonstrating gain, bandwidth, dynamic range, and drift characteristics, as well as measurements of the imaginary component of the input impedance over the relevant frequency range. |
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