Abstract We propose an efficient scheme to generate the maximal entangle states in an atom–cavity system between two three-level atoms in cavity quantum electronic dynamics system based on shortcuts to adiabatic passage. In the accelerate scheme, there is no need to design a time-varying coupling coefficient for the cavity. We only need to tactfully design time-dependent lasers to drive the system into the desired entangled states. Controlling the detuning between the cavity mode and lasers, we deduce a determinate analysis formula for this quantum information processing. The lasers do not need to distinguish which atom is to be affected, therefore the implementation of the experiment is simpler. The method is also generalized to generate a W state. Moreover, the accelerated program can be extended to a multi-body system and an analytical solution in a higher-dimensional system can be achieved. The influence of decoherence and variations of the parameters are discussed by numerical simulation. The results show that the maximally entangled states can be quickly prepared in a short time with high fidelity, and which are robust against both parameter fluctuations and dissipation. Our study enriches the physics and applications of multi-particle quantum entanglement preparation via shortcuts to adiabatic passage in quantum electronic dynamics.
Abstract We propose an efficient scheme to generate the maximal entangle states in an atom–cavity system between two three-level atoms in cavity quantum electronic dynamics system based on shortcuts to adiabatic passage. In the accelerate scheme, there is no need to design a time-varying coupling coefficient for the cavity. We only need to tactfully design time-dependent lasers to drive the system into the desired entangled states. Controlling the detuning between the cavity mode and lasers, we deduce a determinate analysis formula for this quantum information processing. The lasers do not need to distinguish which atom is to be affected, therefore the implementation of the experiment is simpler. The method is also generalized to generate a W state. Moreover, the accelerated program can be extended to a multi-body system and an analytical solution in a higher-dimensional system can be achieved. The influence of decoherence and variations of the parameters are discussed by numerical simulation. The results show that the maximally entangled states can be quickly prepared in a short time with high fidelity, and which are robust against both parameter fluctuations and dissipation. Our study enriches the physics and applications of multi-particle quantum entanglement preparation via shortcuts to adiabatic passage in quantum electronic dynamics.
Abstract We propose an efficient scheme to generate maximally entangled states between two three-level atoms in multi-cavity systems via shortcuts to the adiabatic technique. Two atoms are trapped in spatially separated cavities which are linked through direct coupling and optical fiber coupling, respectively. Time-dependent lasers which are tactfully designed radiate the atoms to drive the evolution rapidly. A determinate analysis solution for this distributed maximally entangled state is achieved by controlling the detuning between the cavity mode and laser fields. Numerical simulations show that the shortcut scheme permits the decoherence which arises from the noisy environment and spontaneous emission to some extent. Meanwhile, the scheme tolerates the imprecision of the experimental parameters, such as evolution time, laser parameters and so on. Our research provided a fast, analytical and feasible technology in non-locality quantum entanglement preparation in quantum electronic dynamics.
We propose an effective scheme of shortcuts to adiabaticity for generating a three-dimensional entanglement of two atoms trapped in a cavity using the transitionless quantum driving (TQD) approach. The key point of this approach is to construct an effective Hamiltonian that drives the dynamics of a system along instantaneous eigenstates of a reference Hamiltonian to reproduce the same final state as that of an adiabatic process within a much shorter time. In this paper, the shortcuts to adiabatic passage are constructed by introducing two auxiliary excited levels in each atom and applying extra cavity modes and classical fields to drive the relevant transitions. Thereby, the three-dimensional entanglement is obtained with a faster rate than that in the adiabatic passage. Moreover, the influences of atomic spontaneous emission and photon loss on the fidelity are discussed by numerical simulation. The results show that the speed of entanglement implementation is greatly improved by the use of adiabatic shortcuts and that this entanglement implementation is robust against decoherence. This will be beneficial to the preparation of high-dimensional entanglement in experiment and provides the necessary conditions for the application of high-dimensional entangled states in quantum information processing.
Quantum information, as a comprehensive subject of quantum mechanics and information science, has a broad theoretical research value and application prospect. As a resource of quantum information, quantum entanglement has been studied thoroughly, which is not only significant to understand the features of quantum mechanics, but also of great value to the development of the method new quantum information processing. Therefore, the generation of entangled state is widely studied theoretically. In comparison to low-dimensional entangled states, multi-dimensional entangled states are not only safe but also efficient and error-tolerant for quantum computation. The adiabatic technique is one of the most widely used and proven techniques in quantum information science. The main advantages of this technique are that it is insensitive to the fluctuation of experimental parameters, and the interaction time of the system is not required to be controled accurately. However, limited by the adiabatic condition, it usually takes relatively long interaction time in scheme via adiabatic technique to achieve the target states. If the required evolution time is too long, the scheme may be useless. To overcome this problem, researchers have done a lot in the field of finding ways to shorten the long interaction time of adiabatic passage. Among these works, the technique named shortcuts to adiabatic passage is a successful work in this field and it has attracted a great deal of attention in recent years. In this paper, based on transitionless quantum driving to construct shortcuts to adiabatic passage, an efficient scheme to fast generate a four-dimensional entangled state of two-atom is proposed. The atoms are respectively trapped in the separate two-mode cavities which are connected by optical fiber. To achieve an alternative physically feasible system, the non-resonant dynamics is adopted to create a Hamiltonian which can exactly drive the system to evolve along the instantaneous eigenstates of the original Hamiltonian. As a result, if the system goes through adiabatic passage, it will evolve in the dark state, not transit to other states. Hence, using transitionless quantum driving to shortcuts to adiabatic passage, the evolutionary time in this scheme is much less than that in other schemes based on traditional adiabatic passage. The rigorous numerical simulations are conducted. The results show that with suitable pulsed laser parameters, this scheme is robust against decoherence arising from fiber decay, cavity decay and atomic spontaneous emission. Moreover, the scheme is more feasible in physics. That is, based on the proposed scheme, a high-fidelity four-dimensional entangled state of two-atom can be achieved.
A scheme is proposed for the fast generation of three-dimensional entanglement between two atoms trapped in two cavities connected by a fiber via invariant-based shortcut to an adiabatic passage. With the help of quantum Zeno dynamics, the invariant-based shortcut technique is applied to the generation of two-atom three-dimensional entanglement. The numerical simulation results show that the target state can be generated in a short time with high fidelity, and the scheme is robust against the decoherence caused by atomic spontaneous emission, photon leakage, and variations in the parameters. Moreover, it may be possible to implement the scheme with the current experimental technology.
A scheme for preparing a three-dimensional entangled state of two atoms is proposed. In the present scheme, two atoms are placed in two cavities that are spatially separated and connected by a fiber. With the help of quantum Zeno dynamics, the shortcuts to adiabaticity can be constructed through transitionless quantum driving to fast achieve the preparation of a three-dimensional entangled state. During this process, we consider the influence of fluctuations about system parameters and various decoherence factors on the fidelity. Numerical simulation results demonstrate that this scheme can not only realize the preparation of a three-dimensional entangled state with a high fidelity, but is also insensitive to parameter fluctuations. Moreover, our scheme can be extended to realize the N-dimensional entanglement of two atoms.
We construct a shortcut to an adiabatic passage in a three-level system by choosing a dressed state acting as an evolutive path. Two designed auxiliary pulses are added into the original pulses to eliminate the couplings between the chosen evolutive-path state and the other two dressed states. The same target state as one gotten by adiabatic passage can be rapidly obtained, and the population of the lossy intermediate state can be controlled by setting proper parameters. Furthermore, as an example, we use this method in the adiabatic-passage scheme [Opt. Express20, 014547 (2012)], a complicated cavity quantum electrodynamics system, to successfully accelerate the generation of the three-dimensional entanglement between a single atom and a Bose-Einstein condensate.