Magnon qubit on double Bose-Einstein condensate

We have proposed a magnon qubit based on coupled configuration of Bose-Einstein condensates (BEC) in two ferromagnetic samples placed closely to each other. We have evaluated the magnon BEC qubit realization in the double BEC scheme where we found a quantum synchronism condition providing an effective Hamiltonian of magnon qubit. It has the form of well-known superconducting Josephson qubit. The possibilities for coherent magnon BEC qubit rotation are analyzed. Implementations of the magnon BEC qubit are considered for small samples and thin ferromagnetic films. Advantages of the proposed macroscopic qubit realization are discussed.