Flying Qubits in Cavity QED

Information in a prospective quantum computer [1, 2] is carried by two-state quantum objects termed qubits. Quantum calculations would be performed by propagating a. wavefunction specifying the state of the qubits through a series of quantum logic gates. An elementary type of gate modifies the state of one qubit depending on the state of another (two-bit controlled rotation). When supplemented by single qubit rotations, such a. gate can serve as a. universal device for quantum computation [3].