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arXiv · 1311.5345

Josephson directional amplifier for quantum measurement of superconducting circuits

Baleegh Abdo·Katrina Sliwa·S. Shankar·Michael Hatridge·Luigi Frunzio·Robert Schoelkopf·Michel Devoret
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Abstract

We have realized a microwave quantum-limited amplifier that is directional and can therefore function without the front circulator needed in many quantum measurements. The amplification takes place in only one direction between the input and output ports. Directionality is achieved by multi-pump parametric amplification combined with wave interference. We have verified the device noise performances by using it to readout a superconducting qubit and observed quantum jumps. With an improved version of this device, qubit and preamplifer could be integrated on the same chip.

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Baleegh Abdo, Katrina Sliwa, S. Shankar, Michael Hatridge, Luigi Frunzio, Robert Schoelkopf, Michel Devoret. 2013-11-21. Josephson directional amplifier for quantum measurement of superconducting circuits. https://doi.org/10.1103/physrevlett.112.167701

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