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arXiv · 2110.13879

Coherent Spin Preparation of Indium Donor Qubits in Single ZnO Nanowires

Maria L. K. Viitaniemi·Christian Zimmermann·Vasileios Niaouris·Samuel H. D'Ambrosia·Xingyi Wang·E. Senthil Kumar·Faezeh Mohammadbeigi·Simon P. Watkins·Kai-Mei C. Fu
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Abstract

Shallow donors in ZnO are promising candidates for photon-mediated quantum technologies. Utilizing the indium donor, we show that favorable donor-bound exciton optical and electron spin properties are retained in isolated ZnO nanowires. The inhomogeneous optical linewidth of single nanowires (60 GHz) is within a factor of 2 of bulk single-crystalline ZnO. Spin initialization via optical pumping is demonstrated and coherent population trapping is observed. The two-photon absorption width approaches the theoretical limit expected due to the hyperfine interaction between the indium nuclear spin and the donor-bound electron.

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Maria L. K. Viitaniemi, Christian Zimmermann, Vasileios Niaouris, Samuel H. D'Ambrosia, Xingyi Wang, E. Senthil Kumar, Faezeh Mohammadbeigi, Simon P. Watkins, Kai-Mei C. Fu. 2021-10-26. Coherent Spin Preparation of Indium Donor Qubits in Single ZnO Nanowires. https://doi.org/10.1021/acs.nanolett.1c04156

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