Spin qubits are powerful, but delicate objects. One of their possible realizations relies on nanomagnets. They are meant to provide a very homogenous and reproducible magnetic field gradient for the qubits. However, their fabrication poses a significant challenge in practice. L. Zaper et al employed a unique combination of fabrication and characterization techniques to address this issue.
On the one hand, they decided to fabricate the nanomagnets using Focused-Electron-Beam-Ion-Deposition (FEBID). FEBID is a resist-free technique and can even be used to make complex three-dimensional nanomagnetic structures. On the other hand, the team chose scanning NV microscopy as a tool to assess the properties of the FEBID nanomagnets.
Using the Qnami ProteusQ and the Magneto PQ, the nanomagnets were…