Coherent Spin Preparation of Indium Donor Qubits in Single ZnO Nanowires

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 line width 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.

Automated summary

Utilizing indium donors, this study demonstrates the favorable optical and electron spin properties in ZnO nanowires. The research shows that the optical line width of single nanowires is comparable to bulk single-crystalline ZnO and successfully achieves spin initialization and observation of coherent population trapping.