A full-vortex flux qubit for charged particle optics

Abstract: We introduce a design of a superconducting flux qubit capable of holding a full magnetic flux quantum $\phi_{0}$, which arguably is an essential property for applications in charged particle optics. The qubit comprises a row of $N$ constituent qubits, which hold a fractional magnetic flux quantum $\phi_{0}/N$. Insights from physics of the transverse-field Ising chain reveal that properly designed interaction between these constituent qubits enables their collective behavior while also maintaining the overall quantumness.