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We propose an alternative scheme of shortcuts to quantum phase gate in a much shorter time based on the approach of Lewis-Riesenfeld invariants in cavity quantum electronic dynamics (QED) systems. This scheme can be used to perform one-qubit phase gate, two-qubit controlled phase gate and also multiqubit controlled phase gate. The strict numerical simulation for some quantum gates are given, and demonstrate that the total operation time of our scheme is shorter than previous schemes and very robustness against decoherence.

Abstract. We theoretically propose an alternative method to realize a deterministic SWAP gate using shortcuts to adiabatic passage based on the approach of LewisRiesenfeld invariants in cavity quantum electronic dynamics (QED). By combining Lewis-Riesenfeld invariants with quantum Zeno dynamics, the SWAP gate can be achieved deterministically. The strict numerical results show that our scheme is a fast and robust approach to achieve SWAP gate.

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Abstract:We propose an adiabatic passage approach to generate two atoms threedimensional entanglement with the help of quantum Zeno dynamics in a timedependent interacting field. The atoms are trapped in two spatially separated cavities connected by a fiber, so that the individual addressing is needless. Because the scheme is based on the resonant interaction, the time required to generate entanglement is greatly shortened. Since the fields remain in vacuum state and all the atoms are in the ground states, the losses due to the excitation of photons and the spontaneous transition of atoms are suppressed efficiently compared with the dispersive protocols. Numerical simulation results show that the scheme is robust against the decoherences caused by the cavity decay and atomic spontaneous emission. Additionally, the scheme can be generalized to generate N -atom three-dimensional entanglement and high-dimensional entanglement for two spatially separated atoms.Keywords: quantum Zeno dynamics · Adiabatic passage · three-dimensional entanglement Quantum entanglement, an interesting and attractive phenomenon in quantum mechanics, plays a significant role not only in testing quantum nonlocality, but also in a variety of quantum information tasks [1][2][3][4][5][6][7][8], such as quantum computing [9-11], teleportation [4], cryptography [1], precision measurements [12] and so on. Recently, high-dimensional entanglement is becoming more and more important since they are more secure than qubit systems, especially in the aspect of quantum key distribution. Besides, it has been demonstrated that violations of local realism by two entangled high-dimensional systems are stronger than

We propose a dressed-state scheme to achieve shortcuts to adiabaticity in atom-cavity quantum electrodynamics for speeding up adiabatic two-atom quantum state transfer and maximum entanglement generation. Compared with stimulated Raman adiabatic passage, the dressed-state scheme greatly shortens the operation time in a non-adiabatic way. By means of some numerical simulations, we determine the parameters which can guarantee the feasibility and efficiency both in theory and experiment. Besides, numerical simulations also show the scheme is robust against the variations in the parameters, atomic spontaneous emissions and the photon leakages from the cavity.

An efficient scheme is proposed for generating n-qubit GreenbergerHorne-Zeilinger states of n superconducting qubits separated by (n − 1) coplanar waveguide resonators capacitively via adiabatic passage with the help of quantum Zeno dynamics in one step. In the scheme, it is not necessary to precisely control the time of the whole operation and the Rabi frequencies of classical fields because of the introduction of adiabatic passage. The numerical simulations for three-qubit Greenberger-Horne-Zeilinger state show that the scheme is insensitive to the dissipation of the resonators and the energy relaxation of the superconducting qubits. The three-qubit Greenberger-Horne-Zeilinger state can be deterministically generated with comparatively high fidelity in the current experimental conditions, though the scheme is somewhat sensitive to the dephasing of superconducting qubits.

We propose a novel deterministic protocol that two senders are capable of remotely preparing arbitrary two-and three-qubit states for a remote receiver using EPR pairs and GHZ state as the quantum channel. Compared with the existing deterministic protocols [An et al. 2011 Phys. Lett. A 375 3570 and Chen et al. 2012 J. Phys. A: Math. Theor. 45 055303], the quantum resources and classical information in our scheme are decreased, and the whole operation process is simplified.