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arXiv · 1904.10652

Quantum Tomography of the Photon-Plasmon Conversion Process in a Metal Hole Array

Lei Tang·Kaimin Zheng·Jiale Guo·Yi Ouyang·Yang Wu·Chuanqing Xia·Long Li·Fang Liu·Yong Zhang·Lijian Zhang·Min Xiao
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Abstract

In the past decades, quantum plasmonics has become an active area due to its potential applications in on-chip plasmonic devices for quantum information processing. However, the fundamental physical process, i.e., how a quantum state of light evolves in the photon-plasmon conversion process, has not been clearly understood. Here, we report a complete characterization of the plasmon-assisted extraordinary optical transmission process through quantum process tomography. By inputting various coherent states to interact with the plasmonic structure and detecting the output states with a homodyne detector, we reconstruct the process tensor of the photon-plasmon conversion process. Both the amplitude and phase information of the process are extracted, which explains the evolution of the quantum-optical state after the coupling with plasmons. Our experimental demonstration constitutes a fundamental block for future on-chip applications of quantum plasmonic circuits.

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Lei Tang, Kaimin Zheng, Jiale Guo, Yi Ouyang, Yang Wu, Chuanqing Xia, Long Li, Fang Liu, Yong Zhang, Lijian Zhang, Min Xiao. 2019-04-24. Quantum Tomography of the Photon-Plasmon Conversion Process in a Metal Hole Array. https://doi.org/10.1364/oe.27.013809

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