Proposal for coherent coupling of Majorana and fluxonium qubits

We propose to use an ancilla fluxonium qubit to interact with a Majorana qubit hosted by a topological 1D wire. The coupling is obtained using the Majorana qubit controlled $4pi$ Josephson effect to flux bias the fluxonium qubit. We demonstrate how this coupling can be used to sensitively identify topological superconductivity, to measure the state of the Majorana qubit, to construct 2-qubit operations, and to implement quantum memories with topological protection.