Realization of a general quantum cloning machine via cavity-assisted interaction

Abstract

We present a scheme to realize a general quantum cloning machine via cavityassisted interaction. First, this scheme can prepare entangled states of three remote trapped atoms including the W state and the GHZ state. Based on this approach, the quantum information carried by a photon pulse or a trapped atom can be copied to other two trapped atoms. According to the known information of the initial state, the equipment can provide the optimal symmetric (asymmetric) universal and phase-covariant quantum cloning. Further, via the cavity input-output process, the quantum cloning can be realized with high fidelity, even if the atom is not localized in the Lamb-Dicke regime.

Implementing a quantum cloning machine in separate cavities via the optical coherent pulse as a quantum communication bus

“…The distinct advantage of our scheme is that (1) the quantum information is encoded into discrete variables (DVs), namely, the electron-spin system in the individual cavity while the CVs mode, the optical coherent pulse, plays the role of a quantum communication bus to mediate interactions. In those schemes [28][29][30][31][32][33][34][35][36] with single-photon-based qubus, enormous difficulties arise due to the requirements on the generation and detection of the photons. As is known to all, the performance of a successful near-deterministic gate is indispensable from efficient detectors which unambiguously detect a single photon.…”

“…In the present scheme, the optical coherent pulse, called a quantum communication 'Corresponding author: yeliu@ahu.edu.cn bus (qubus), sequentially interacts with two electron-spin systems placed in the separate cavities. However, in those schemes [28][29][30][31][32][33][34][35][36] with single-photon-based qubus, enormous difficulties appear due to the demanding requirements on the generation and detection of the photons. The present approach can circumvent this obstacle by using the continuous variables (CVs) mode as qubus, namely, the optical coherent pulse.…”

“…Thus it plays only the role of a catalyst. The measurement-free operation for qubus avoids measurement-induced errors in contrast to the previous schemes [28][29][30] and the present cloning transformation becomes deterministic without measurement-result-dependent postselection [37][38][39] or any feedforward operations on the qubits. Due to the deterministic and measurement-free opera tion, the present scheme has high efficiency with high success probability.…”

Multipurpose Quantum Simulator Based on a Hybrid Solid-State Quantum Device

“…In recent years, much effort has been made to study QCM theoretically and experimentally, including the universal QCM [4][5][6][7], probabilistic quantum cloning [3,8], state-dependent cloning [9], phase-covariant quantum cloning [10][11][12], quantum cloning in separate cavities via the optical coherent pulse as a quantum communication bus [13], economical state-dependent telecloning [14,15], and quantum jointly assisted cloning [16].…”

Quantum information processing in collective-rotating decoherence-free subspace

“…(ii) Besides the logic gate, many other QIP proposals in the CRDFS, such as Bell-state measurement (BSM) and quantum information transfer, are also proposed in our proposal. (iii) The presented hybrid-controlled-phase-flip (HCPF) gate can be used to other QIP tasks in the CRDFS, such as quantum cloning [24], quantum entanglement generation and quantum teleportation.…”