## Superconductor-ferromagnet junction phase qubit

Noh, Tae-Wan
Kim, Mun Dae
Sim, H. -S.
##### Description
We propose a scheme for a phase qubit in an SIFIS junction, consisting of bulk superconductors (S), a proximity-induced ferromagnet (F), and insulating barriers (I). The qubit state is constituted by 0 and $\pi$ phase states of the junction, in which the charging energy of the junction leads to the superposition of the two states. The qubit is operated by the gate voltage applied to the ferromagnet, and insensitive to the decoherence sources existing in other superconducting qubits. We discuss a scalable scheme for qubit measurement and tunable two-qubit coupling.
Comment: 3 pages, 3 figures
##### Keywords
Condensed Matter - Superconductivity