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arXiv · 1207.4403

Realization of GHz-frequency impedance matching circuits for nano-scale devices

G. Puebla-Hellmann·A. Wallraff
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Abstract

Integrating nano-scale objects, such as single molecules or carbon nanotubes, into impedance transformers and performing radio-frequency measurements allows for high time-resolution transport measurements with improved signal-to-noise ratios. The realization of such transformers implemented with superconducting transmission lines for the 2-10 GHz frequency range is presented here. Controlled electromigration of an integrated gold break junction is used to characterize a 6 GHz impedance matching device. The real part of the RF impedance of the break junction extracted from microwave reflectometry at a maximum bandwidth of 45 MHz of the matching circuit is in good agreement with the measured direct current resistance.

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G. Puebla-Hellmann, A. Wallraff. 2012-07-18. Realization of GHz-frequency impedance matching circuits for nano-scale devices. https://doi.org/10.1063/1.4739451

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