Coherence properties of shallow donors in ZnO

ORAL

Abstract

The donor system in ZnO is a promising potential qubit for spin-based quantum information processing. It has similar advantages as the well-studied phosphorus donors in Si, i.e. high homogeneity, long coherence time, and strong donor nucleus-electron interaction, with the additional advantage that ZnO donors are optically coupled to donor-bound excitons. Here we present optical measurements of the Ga donor electron spin T1, T2*, and T2. We find the longitudinal spin relaxation time T1 is inversely proportional to the external magnetic field with a relationship ~B-3.5. The longest T1 we measure is ~0.1 s at 2.5 T. Due to the B-3.5 relationship, we expect T1 will exceed 1 s at fields lower than 1 T. We measure a T2* of ~20 ns and a spin echo decoherence time T2 of ~30 μs, which may be limited by instantaneous diffusion due to the high donor concentration (~1017 cm-3) or the spectral diffusion due to flip-flop of the surrounding Zn67 nuclear spins (4.1% of natural Zn). We describe these experiments as well as present a path toward single Zn donor isolation and increased coherence times.

*This material is based upon work supported by the NSF under Grant No. 1150647. K.-M. F. also acknowledges the support from the Research Corporation for Science Advancement as a Cottrell Scholar.

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Presenters

  • Xiayu Linpeng

    • Department of Physics, University of Washington

Authors

  • Xiayu Linpeng

    • Department of Physics, University of Washington

  • Maria Viitaniemi

    • Department of Physics, University of Washington

  • Yusuke Kozuka

    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), the University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), Univ. of Tokyo
    • Applied Physics, University of Tokyo

  • Cameron Johnson

    • Department of Physics, University of Oregon

  • Joseph Falson

    • Max Planck Institute for Solid State Research

  • Atsushi Tsukazaki

    • Institute for Materials Reaserch, Tohoku University
    • Tohoku Univ
    • Institute for Materials Research, Tohoku University
    • IMR, Tohoku University
    • Institute for Materials Research
    • Tohoku University
    • Tohoku Univ.

  • Masashi Kawasaki

    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), the University of Tokyo
    • Univ of Tokyo
    • The University of Tokyo
    • Department of Applied Physics and Quantum Phase Electronics Center, University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), Univ. of Tokyo
    • Applied Physics, University of Tokyo
    • Department of Applied Physics, The University of Tokyo
    • Department of Applied Physics, University of Tokyo

  • Kai-Mei Fu

    • Department of Physics and Department of Electrical Engineering, University of Washington
    • University of Washington