Year: 2018
Type: article
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%.
Source: npj Quantum Information
Authors: James G. Titchener, Markus Gräfe, René Heilmann, Alexander S. Solntsev, Alexander Szameit, Andrey A. Sukhorukov
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,290
Awards: Nonlinear nano-photonic structures for frequency conversion: from classical to quantum applications, G1870652944, G2625860514, Optical wavelength conversion in nonlinear dielectric nano-resonators, Active photonic and plasmonic components based on parity-time symmetry, G6621971528, G789357589
OpenAlex ID: W2560259994