Complex sentence: As in a superconducting electrode, the phase and the charge are conjugate variables, there exists three families of superconducting qubits, depending if the charge, the phase or neither of the two are good quantum numbers.
Split into simpler sentences: As in a superconducting electrode, the phase and the charge are conjugate variables. There exist three families of superconducting qubits, depending on whether the charge, the phase, or neither of the two are good quantum numbers.