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arXiv:2112.13262

Manifestations of changes in entanglement and onset of synchronization in tomograms

Soumyabrata Paul, S. Lakshmibala, V. Balakrishnan, S. Ramanan

Published Dec 25, 2021• 0 citations
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Abstract

Quantum state reconstruction for continuous-variable systems such as the radiation field poses challenges which arise primarily from the large dimensionality of the Hilbert space. Many proposals for state reconstruction exist, ranging from standard reconstruction protocols to applications of machine learning. No universally applicable protocol exists, however, for extracting the Wigner function from the optical tomogram of an arbitrary state of light. We establish that nonclassical effects such as entanglement changes during dynamical evolution and the onset of quantum synchronization are mirrored in qualitative changes in optical tomograms themselves, circumventing the need for state reconstruction for this purpose.

DOI
10.48550/arxiv.2112.13262

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In quantum technologies, continuous-variable systems offer advantages over their discrete counterparts. However, continuous-variable tomography suffers from exponentially growing sample complexity. We propose protocols using quantum mirrors to transfer the complete information of incident photonic states onto a control atomic system. This enables full photonic state characterization through measurements on the control atom alone, realized via kernel functions, direct wavefunction reconstruction, and pointwise Wigner function measurements. Our approach overcomes the limitations of conventional photon counting, statistical inference, and inverse transformation, providing a robust framework for benchmarking and verifying non-Gaussian states in continuous-variable quantum optics.
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