Based on the relevant concepts of quantum entanglement and the basic principles of quantum information, this paper focuses on the generation process of three-body high-dimensional entangled states between magnets and photons in the Uptime (PT)-symmetry-breaking phase, and clarifies the dissipation and evolution process of three-body high-dimensional entangled states for the system in this paper.Finally, it is generalized to the hybrid photon-magneton oscillator system in the action of electromagnetic waves to explore whether the perfect transmission of quantum states can be realized under the condition of one-dimensional magnetic oscillator openchain arrangement.The results show that the introduction of three-body high-dimensionality can not only effectively enhance the entanglement, but also effectively enhance the entanglement resistance to environmental interference, so that the system can operate stably in a wider range of parameters.The scheme in this paper can utilize the optical cavity dissipation to keep the quantum state stable at the receiving end.In addition, the spontaneous radiation of atoms is significantly suppressed due to the adiabatic elimination of the excited state, which makes the scheme more robust.Meanwhile, based on the existing experimental techniques, the scheme has high experimental feasibility, and the fidelity of its transmitted state at the receiving end can reach more than 99.74%.
Based on the relevant concepts of quantum entanglement and the basic principles of quantum information, this paper focuses on the generation process of three-body high-dimensional entangled states between magnets and photons in the Uptime (PT)-symmetry-breaking phase, and clarifies the dissipation and evolution process of three-body high-dimensional entangled states for the system in this paper.Finally, it is generalized to the hybrid photon-magneton oscillator system in the action of electromagnetic waves to explore whether the perfect transmission of quantum states can be realized under the condition of one-dimensional magnetic oscillator openchain arrangement.The results show that the introduction of three-body high-dimensionality can not only effectively enhance the entanglement, but also effectively enhance the entanglement resistance to environmental interference, so that the system can operate stably in a wider range of parameters.The scheme in this paper can utilize the optical cavity dissipation to keep the quantum state stable at the receiving end.In addition, the spontaneous radiation of atoms is significantly suppressed due to the adiabatic elimination of the excited state, which makes the scheme more robust.Meanwhile, based on the existing experimental techniques, the scheme has high experimental feasibility, and the fidelity of its transmitted state at the receiving end can reach more than 99.74%.
Based on the characteristics of superposition, entanglement, non-locality and non-clonality of quantum mechanics, quantum information science can break through the physical limits of classical information and open up a new information processing function different from classical electromagnetic application methods. Due to the advantages of high-energy single photon in practical applications, the research and application of optical quantum information technology dominates the development of current quantum information technology. However, the free-space transmission of light waves is greatly affected by weather conditions and atmospheric particles. Comparing with other wave bands, classical microwave signal shows good penetration ability when transmitting in free space. By introducing quantum mechanics, microwave signal also exhibits non-classical merits. As quantum microwave signal inherits both classical transmission performance and quantum non-classical features, it can be utilized as a significant signal source for diverse applications in microwave domain, such as quantum communication, quantum navigation and quantum radar, which are based on quantum technologies in large scale and dynamic free space transmission. There are three main experimental platforms on which quantum microwave is studied and produced. They are cavity quantum electrodynamics(C-QED) system, circuit quantum electrodynamics(c-QED) system, and cavity electro-opto-mechanical(EOM) system, involving with several nonlinear effects such as Kerr effect, Casimir effect, three-wave mixing, etc. In this paper, the setups of these platforms and the preparation principles are introduced. Meanwhile, the preparation principles and methods of microwave single photon, entangled microwave photons, squeezed microwave fields and entangled microwave fields are summarized and analyzed in detail from three aspects. The present status of experimental progress in the relevant fields are summarized and listed as well. Besides, key problems in the application of quantum navigation in free space utilizing quantum microwave are probed. Among them, the most pressing ones are preparation ability, decoherence in transmission and detection of entangled quantum microwave signals, which are also discussed and analyzed in this paper. Finally, we look forward to the future development of quantum microwave technology. It mainly consists of manufacturing microwave detectors with high efficiency, designing thermal photon filters, and developing suitable antennas. We hope that this study can provide useful reference for scholars who are engaged in or interested in research related to quantum microwave technologies.
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.
A scheme is proposed for generating a multiparticle three-dimensional entangled state by appropriately adiabatic evolutions, where atoms are respectively trapped in separated cavities so that individual addressing is needless. In the ideal case, losses due to the spontaneous transition of an atom and the excitation of photons are efficiently suppressed since atoms are all in ground states and the fields remain in a vacuum state. Compared with the previous proposals, the present scheme reduces its required operation time via simultaneously controlling four classical fields. This advantage would become even more obvious as the number of atoms increases. The experimental feasibility is also discussed. The successful preparation of a high-dimensional multiparticle entangled state among distant atoms provides better prospects for quantum communication and distributed quantum computation.
High-dimensional quantum systems, known as qudits with dimension d>2, possess the capability to encode and process more information than traditional two-dimensional qubits. Entangled states serve as crucial resources for both quantum computation and quantum communication. On the basis of circuit quantum electrodynamics (QED) systems, we introduce an efficient scheme to deterministically generate high-dimensional multipartite entangled states of hybrid qutrits (d=3). Assuming a simple initial state has already been prepared with the use of local operations, our method requires only a single step to produce hybrid Greenberger-Horne-Zeilinger (GHZ) entangled states among circuit QED systems consisting of superconducting qutrits and a superconducting cavity. Remarkably, the number of steps and the operational time remain constant as the number of qutrits increases, highlighting the efficiency and scalability of our approach. Using numerical simulations for a three-dimensional hybrid GHZ state of seven qutrits, we demonstrate the feasibility of our scheme and study the effects of various parameters on the fidelity. The importance of this research is in directing the experimental creation of multipartite, high-dimensional, and hybrid GHZ states, which can then be used to enhance quantum communication protocols and computational processes.
In the current fields of quantum information processing and quantum computing, fast and accurate quantum state manipulation and preparation have been of keen interest to researchers, and their potential applications are mainly in quantum measurement, quantum information, quantum communication, and quantum sensing.In this paper, the Hilbert space of a bipartite state system is unfolded by four Bell state entanglement bases and the result is projected to the subsystem to obtain a mixed state.A quantum approximation algorithm is proposed to provide a solution to the combinatorial optimization problem, and based on the workflow of the quantum approximation optimization algorithm, an improvement is proposed to the quantum approximation optimization algorithm to solve the constrained problem using the quadratic unconstrained binary optimization method.Based on the theory of cavity magnetism, the hybrid quantum system model is constructed, and the calculation method of Hamiltonian quantity is proposed.Combined with the quantum entanglement optimal path calculation of UQAOA algorithm, the optimal value of time-microwave entanglement ac E is obtained at r=0.234, so the compression parameter r=0.2 is used in the calculation.Based on the UQAOA algorithm for the analysis of the transmission characteristics of the generated OMA wave in air and the transmission optimization problem, the simulation obtains the reflection coefficient is slightly lower than that of the test, and the maximal error error is controlled at ±7.5dB around, and the two results are basically in agreement.
Quantum state transfer plays an important role in quantum information processing, and it has been obtained many of the theoretical and experimental triumphs. But designing a dissipation-assisted scheme to transfer a quantum state is still by no means trivial. Here we put forward an easier scheme to dissipatively transfer an arbitrary quantum state from a sender to a receiver with two four-level atoms and three lasers in a lossy coupled-cavity array, and make the quantum state stable at the receiver via the photon loss of optical cavities. Owing to the assistance of the dissipation, the target state becomes the steady state of the whole process. Thus there is no requirement on external time-dependent controls. Furthermore, the atomic spontaneous emission can be significantly suppressed as the adiabatic elimination of the excited states. We also discuss the experimental feasibility of this scheme with the current experimental technologies and a high fidelity of the transferred state in the receiver can be above 98%.