  We describe an adiabatic state transfer mechanism that allows for
high-fidelity transfer of a microwave quantum state from one cavity to another
through an optical fiber. The conversion from microwave frequency to optical
frequency is enabled by an optomechanical transducer. The transfer process
utilizes a combined dark state of the mechanical oscillator and fiber modes,
making it robust against both mechanical and fiber loss. We anticipate this
scheme being an enabling component of a hybrid quantum computing architecture
consisting of superconducting qubits with optical interconnects.
