Optical and microstructural characterization of epitaxial Er-doped CeO<sub>2</sub> on silicon

ORAL

Abstract

Erbium-doped cerium oxide (Er:CeO2) is a promising defect-host combination for applications in quantum memories for wide-area fiber optic-based quantum networks, due to the telecom-compatible (~1.5 μm) 4f-4f optical transition of Er, predicted long electron spin coherence time for defects in CeO2,1 and small lattice mismatch between silicon and CeO2. Here we report on epitaxial Er:CeO2 thin films grown on silicon by molecular beam epitaxy, with Er doping in the 1-100 ppm regime.2 We verify the CeO2 host structure via thorough microstructural study, and then characterize the spin and optical properties of the embedded Er3+ ions as a function of doping density. Studying the Z1-Y1 optical transition near 1530 nm at 3.5 K with 2-3 ppm Er, we find spectral diffusion-limited homogeneous linewidths as narrow as 5 MHz, along with inhomogeneous linewidths of 10 GHz and optical excited state lifetimes of 3.5 ms; further measurements at 4 K yield EPR linewidths of 250 MHz. We then discuss routes for optical and spin linewidth improvement via growth optimization and post-growth treatment.

(1) S. Kanai, et al. PNAS. 119, e2121808119 (2022).

(2) G. Grant, et al. arXiv:2309.16644 (2023).

*This work is primarily supported by Q-NEXT, a U.S. Department of Energy Office of Science National Quantum Information Science Research Center, with additional support from the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division.

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Publication: G. Grant, et al., "Optical and microstructural characterization of Er3+ doped epitaxial cerium oxide on silicon", arXiv:2309.16644 (2023), under review with APL Materials.

Presenters

  • Gregory Grant

    • University of Chicago / Argonne National Lab
    • University of Chicago

Authors

  • Gregory Grant

    • University of Chicago / Argonne National Lab
    • University of Chicago

  • Jiefei Zhang

    • Argonne National Laboratory

  • Ignas Masiulionis

    • University of Chicago / Argonne National Lab
    • University of Chicago/Argonne National Laboratory
    • University of Chicago

  • Swarnabha Chattaraj

    • Argonne National Laboratory

  • Kathryn E Sautter

    • IQE
    • Argonne National Laboratory

  • Sean E Sullivan

    • Argonne National Laboratory

  • Rishi Chebrolu

    • University of Chicago

  • Yuzi Liu

    • Argonne National Laboratory

  • Jessica B Martins

    • Argonne National Laboratory

  • Jens Niklas

    • Argonne National Lab
    • Argonne National Laboratory

  • Alan M Dibos

    • Argonne National Laboratory
    • Argonne National Lab

  • Sumit Kewalramani

    • Northwestern University

  • John W Freeland

    • Argonne National Laboratory

  • Jianguo Wen

    • Argonne National Laboratory

  • Oleg G Poluektov

    • Argonne National Lab
    • Argonne National Laboratory

  • F. Joseph F Heremans

    • Argonne National Laboratory
    • Argonne National Lab
    • Argonne
    • University of Chicago

  • David D Awschalom

    • University of Chicago

  • Supratik Guha

    • Argonne National Laboratory
    • University of Chicago/Argonne National Laboratory