Scalable on-chip quantum state tomography

James G. Titchener*, Markus Gräfe, René Heilmann, Alexander S. Solntsev, Alexander Szameit, Andrey A. Sukhorukov

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    54 Citations (Scopus)

    Abstract

    Quantum information systems are on a path to vastly exceed the complexity of any classical device. The number of entangled qubits in quantum devices is rapidly increasing, and the information required to fully describe these systems scales exponentially with qubit number. This scaling is the key benefit of quantum systems, however it also presents a severe challenge. To characterize such systems typically requires an exponentially long sequence of different measurements, becoming highly resource demanding for large numbers of qubits. Here we propose and demonstrate a novel and scalable method for characterizing quantum systems based on expanding a multi-photon state to larger dimensionality. We establish that the complexity of this new measurement technique only scales linearly with the number of qubits, while providing a tomographically complete set of data without a need for reconfigurability. We experimentally demonstrate an integrated photonic chip capable of measuring two- and three-photon quantum states with statistical reconstruction fidelity of 99.71%.

    Original languageEnglish
    Article number19
    Journalnpj Quantum Information
    Volume4
    Issue number1
    DOIs
    Publication statusPublished - 1 Dec 2018

    Fingerprint

    Dive into the research topics of 'Scalable on-chip quantum state tomography'. Together they form a unique fingerprint.

    Cite this