Popis: |
A scheme is proposed for the physical realization of a quantum probabilistic cloning machine.First,with two superconducting quantum interference devices (SQUIDs) embedded in a high-Q cavity used as the original and target qubits respectively,and the cavity field as the measurement qubit,the unitary evolution required for the cloning machines is realized through multiple interactions of SQUID with the cavity or classical microwave pulses.Then the state reduction is implemented by mapping the cavity state onto another SQUID and measuring the magnetic flux of the SQUID,thus realizing the exact cloning of quantum states with optimal success probability.In this scheme,two–photon Raman resonance process is used to increase the single qubit operation rate,and the total operation time is far less the time of spontaneous decay and cavity decay.Therefore this scheme is experimentally feasible. |