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arXiv · 1711.11569

Single-Shot Quantum Non-Demolition Detection of Itinerant Microwave Photons

Jean-Claude Besse·Simone Gasparinetti·Michele C. Collodo·Theo Walter·Philipp Kurpiers·Marek Pechal·Christopher Eichler·Andreas Wallraff
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Abstract

Single-photon detection is an essential component in many experiments in quantum optics, but remains challenging in the microwave domain. We realize a quantum non-demolition detector for propagating microwave photons and characterize its performance using a single-photon source. To this aim we implement a cavity-assisted conditional phase gate between the incoming photon and a superconducting artificial atom. By reading out the state of this atom in single shot, we reach an internal photon detection fidelity of 71%, limited by the coherence properties of the qubit. By characterizing the coherence and average number of photons in the field reflected off the detector, we demonstrate its quantum non-demolition nature. We envisage applications in generating heralded remote entanglement between qubits and for realizing logic gates between propagating microwave photons.

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Jean-Claude Besse, Simone Gasparinetti, Michele C. Collodo, Theo Walter, Philipp Kurpiers, Marek Pechal, Christopher Eichler, Andreas Wallraff. 2017-11-30. Single-Shot Quantum Non-Demolition Detection of Itinerant Microwave Photons. https://doi.org/10.1103/physrevx.8.021003

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