共查询到20条相似文献,搜索用时 15 毫秒
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Jin-Lei Wu Yan Wang Jin-Xuan Han Shi-Lei Su Yan Xia Yongyuan Jiang Jie Song 《Frontiers of Physics》2022,17(2):22501
A dynamics regime of Rydberg atoms, unselective ground-state blockade (UGSB), is proposed in the context of Rydberg antiblockade (RAB), where the evolution of two atoms is suppressed when they populate in an identical ground state. UGSB is used to implement a SWAP gate in one step without individual addressing of atoms. Aiming at circumventing common issues in RAB-based gates including atomic decay, Doppler dephasing, and fluctuations in the interatomic coupling strength, we modify the RAB condition to achieve a dynamical SWAP gate whose robustness is much greater than that of the nonadiabatic holonomic one in the conventional RAB regime. In addition, on the basis of the proposed SWAP gates, we further investigate the implementation of a three-atom Fredkin gate by combining Rydberg blockade and RAB. The present work may facilitate to implement the RAB-based gates of strongly coupled atoms in experiment. 相似文献
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Jun Wang Wan-Ting He Cong-Wei Lu Yang-Yang Wang Qing Ai Hai-Bo Wang 《Annalen der Physik》2023,535(10):2300138
Due to the long coherence time and efficient manipulation, the surface electron (SE) provides a perfect 2D platform for quantum computation and quantum simulation. In this work, a theoretical scheme to realize the controlled-NOT gate is proposed, where the two-qubit system is encoded on the four-level Rydberg structure of SE. The state transfer is achieved by a three-level structure with an intermediate level. By simultaneously driving the SE with two external electromagnetic fields, the dark state in the electromagnetically induced transparency effect is exploited to suppress the population of the most dissipative state and increase the robustness against dissipation. The fidelity of the scheme is 0.9989 with experimentally achievable parameters. 相似文献
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A scheme to prepare a 3D entangled state between a pair of Rydberg atoms via dissipative dynamics and electromagnetic induced transparency associated with the single-atom dark state is proposed. The prepared entangled state is the dark state of the whole system. The scheme is also feasible regardless of initial purity or mixed state. Since the proposed scheme is based on the Rydberg block regime, the Rydberg–Rydberg interaction strength does not need to satisfy a certain relation with laser detuning, which is very different to the Rydberg-antiblock-based dissipative schemes. One group of Rydberg states and corresponding parameters to simulate the fidelity are used, which verify the feasibility of the scheme. 相似文献
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The quantum swap gate is one of the most useful gates for quantum computation. Two-qubit entanglement and a controlled-NOT quantum gate in a neutral Rydberg atom system have been achieved in recent experiments. It is therefore very interesting to propose a scheme here for swapping a quantum state between two trapped neutral atoms via the Rydberg blockade mechanism. The atoms interact with a sequence of laser pulses without individual addressing. The errors of the swap gate due to imprecision of pulse length, finite Rydberg interaction, and atomic spontaneous emission are discussed. 相似文献
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A theoretical calculation is carried out for the spectrum of barium Rydberg atom in an external magnetic field. Using an effective approach incorporating quantum defect into the centrifugal term in the Hamiltonian, we reexamine the reported spectrum of barium Rydberg atom at a magnetic field of 2.89 T [J. Phys. B 28 L537 (1995)]. Our calculation employs B-spline basis expansion and complex coordinate rotation techniques. For single photon absorption from the ground 6s2 to 6snp Rydberg states, the spectrum is not influenced by quantum defects of channels ns and nd. The calculation is in agreement with the experimental observation until the energy reaches E=-60 cm-1. Up beyond in energy, closer to the threshold, the calculated and experimental results do not agree with each other, possible reasons for their discrepancies are discussed. Our study affirms an energy range where the diamagnetic spectrum of barium atom can be explained thoroughly using a hydrogen model potential. 相似文献
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基于成熟的光纤激光器、光纤放大器及高效激光频率转换技术,我们在实验中研制了一套瓦级输出的窄线宽连续波单频可调谐318.6 nm紫外激光系统,并在室温铯原子气室中实现了6S_(1/2)—nP_(3/2)(n=70—94)单光子跃迁里德伯激发.借助由铯原子6S_(1/2)(F=4)基态、6P_(3/2)(F′=5)激发态和nP_(3/2)(n=70—94)里德伯态构成的V型三能级系统,通过频率锁定于铯原子6S_(1/2)(F=4)—6P_(3/2)(F′=5)超精细跃迁的852.3 nm探测光束的吸收减弱信号获得了里德伯态的信息,并利用高精度波长计测量了铯原子nP_(3/2)(n=70—94)里德伯态的量子亏损值.经过与理论计算值的变化趋势进行对比,我们认为由于原子气室的里德伯屏蔽效应并不能完全屏蔽外部直流电场,铯原子气室内存在残余的直流电场,影响了对里德伯态的量子亏损值的实验测量.利用残余直流电场的Stark效应理论模型及其与有效主量子数n*的依赖关系,对铯原子里德伯态的量子亏损实验测量值进行了修正.修正后的铯原子nP_(3/2)(n=70—94)态量子亏损测量值为3.5591±0.0007,与理论计算值相吻合. 相似文献
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Measurement of the argon-gas-induced broadening and line shifting of the barium Rydberg level 6s24d 1D2 by two-photon resonant nondegenerate four-wave mixing 下载免费PDF全文
We apply two-photon resonant nondegenerate four-wave mixing with a resonant intermediate state to the obser-vation of the broadening and shifting of the barium Rydberg level 6s24d 1^D2 by collision with argon. The collision broadening and shifting cross sections are measured. This technique is purely optical, and can investigate the pressure dependence of the transverse relaxation rate-P21 between the Rydberg state and an intermediate state, as well as the transverse relaxation rate F20 between the Rydberg state and the ground state. 相似文献
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利用Rydberg原子作为微波传感器实现了微弱场的测量与通信.在铯原子蒸气池中,相向传输的探测光(852 nm)和耦合光(510 nm)与铯原子相互作用形成阶梯型三能级电磁感应透明光谱,用于实现Rydberg原子的光学探测.频率约为2.19 GHz的强微波场作为本地场(EL),共振耦合相邻的两个Rydberg能级|68D5/2>和|69P3/2>,与具有一定失谐δf的待测微弱信号场(Es)同时作用于Rydberg原子.Rydberg原子作为微波混频器可直接读出两束微波的差频信号,实现待测信号场的高灵敏探测,对应的最小测量值为E0=1.7μV/cm,频率分辨率小于1 Hz.在此基础上,对微弱信号场进行编码,实验上很好地还原了加载到微波弱场上的基带信号,测量的传输带宽达200 MHz,实现了微弱场条件下的通信. 相似文献
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Luis S. Yagüe Bosch Tim Ehret Francesco Petiziol Ennio Arimondo Sandro Wimberger 《Annalen der Physik》2023,535(12):2300275
A shortcut-to-adiabatic protocol for the realization of a fast and high-fidelity controlled-phase gate in Rydberg atoms is developed. The adiabatic state transfer, driven in the high-blockade limit, is sped up by compensating nonadiabatic transitions via oscillating fields that mimic a counterdiabatic Hamiltonian. High fidelities are obtained in wide parameter regions. The implementation of the bare effective counterdiabatic field, without original adiabatic pulses, enables to bypass gate errors produced by the accumulation of blockade-dependent dynamical phases, making the protocol efficient also at low blockade values. As an application toward quantum algorithms, how the fidelity of the gate impacts the efficiency of a minimal quantum-error correction circuit is analyzed. 相似文献
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Implementation of quantum phase gate between two atoms via Rydberg antiblockade and adiabatic passage 下载免费PDF全文
Combining adiabatic passage and Rydberg antiblockade, we propose a scheme to implement a two-qubit phase gate between two Rydberg atoms. Detuning parameters between frequencies of atomic transitions and those of the corresponding driving lasers are carefully chosen to offset the blockade effect of two Rydberg atoms, so that an effective Hamiltonian,representing a single-photon detuning L-type three-level system and concluding the quantum state of two Rydberg atoms excited simultaneously, is obtained. The adiabatic-passage technique, based on the effective Hamiltonian, is adopted to implement a two-atom phase gate by using two time-dependent Rabi frequencies. Numerical simulations indicate that a high-fidelity two-qubit p-phase gate is constructed and its operation time does not have to be controlled accurately. Besides,owing to the long coherence time of the Rydberg state, the phase gate is robust against atomic spontaneous emission. 相似文献
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A protocol to generate atomic singlet state of three atoms is proposed. The strong Rydberg interactions between atoms mediate the multi-qubit operations and help to simplify the dynamics of the system. The effective Hamiltonian is constructed in the regime of Rydberg blockade and the evolution path is built up from an initial state to the target singlet state via the Lie-transform-based pulse design. Numerical simulations show the protocol can produce atomic singlet state with high fidelity and holds robustness against several types of experimental imperfections. Therefore, it may provide some useful results for the generation of singlet states in atomic system. 相似文献
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We observe strong energy-dependent quantum defects in the scaled-energy Stark spectra for |M| = 1 Rydberg states of barium atoms at three scaled energies: ε = 2.000,ε = 2.500 and ε = 3.000.In an attempt to explain the observations,theoretical calculations of closed orbit theory based on a model potential including core effect are performed for non-hydrogenic atoms.While such a potential has been uniformly successful for alkali atoms with a single valence electron,it fails to match experimental results for barium atoms in the 6snp Rydberg states with two valence electrons.Our study points out that this discrepancy is due to the strong perturbation from the 5d8p state,which voids the simple approximation for constant quantum defects of principle quantum number n. 相似文献
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以Nd:YAG激光器的二倍频输出光为抽运光,其三倍频输出抽运的光学参量发生/放大器输出光为探测光,利用光学-光学双色双共振多光子离化光谱技术(OODR-MPI),获得了NO2分子在605—675nm探测光波长范围内的多光子离化激发谱. 通过对NO2分子离化机理的分析,确定了在此波长区间,NO2分子经1+3+1双共振多光子过程离化,离化通道为NO2(X2A1)hν
关键词:
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光学-光学双共振多光子离化谱
里德伯态
分子常数 相似文献
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A computational procedure for controlling the stochastic ionization of one-dimensional single electron Rydberg atoms in the correspondence principle regime is developed. Using our procedure it is possible to suppress excitation and ionization of the one-dimensional Rydberg atom even in strong microwave fields for which ionization would otherwise be instantaneous. 相似文献
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基于五步激光共振激发,经由中间态(Xe) 5d6d~3F_2的一价镧离子光谱,分析了该实验谱,确定了一价镧离子一强一弱两个自电离里德伯系列.同时利用多通道量子亏损理论(MQDT)框架下的相对论多通道理论(RMCT)计算,标识了这两个自电离里德伯系列,强的自电离里德伯系列标识为5dnp(5/2,1/2)_3和/或5dnp(5/2,1/2)_2,弱系列标识为为5dnf(5/2,5/2)_3和/或5dnf(5/2,5/2)_2.根据实验谱峰数据,发现有效量子数很高时,里德伯和自电离里德伯能级量子数亏损随激发能量不平滑变化,并分析了可能的原因. 相似文献
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T. Kopyciuk 《Physics letters. A》2010,374(34):3464-3467
A protocol for deexcitation of one-dimensional high Rydberg states with the use of a chirped train of half-cycle pulses is given. It is found that the parameters of the efficiently deexciting train are directly related to the phenomenon of the dynamical stabilization of the initial state. Finally, numerical calculations are presented to demonstrate the efficiency of the protocol. The protocol allows to deexcite Rydberg atoms to states lying just above the ground one. 相似文献