  We demonstrate experimentally the creation and measurement of an entangled
state between a microscopic two level system and a macroscopic superconducting
resonator where their indirect interaction is mediated by an artificial atom, a
superconducting persistent current qubit (PCQB). We show that the microscopic
two level system, formed by a defect in an oxide layer, exhibits an order of
magnitude longer dephasing time than the PCQB, while the dephasing time of the
entangled states between the microscopic two level system and macroscopic
superconducting resonator is significantly longer than the dephasing time in
the persistent current qubits. This demonstrates the possibility that a qubit
of moderate coherence properties can be used in practice to address low
decoherence quantum memories by connecting them to macroscopic circuit QED
quantum buses, leading future important implications for quantum information
processing tasks.
