Dissipative preparation of multipartite Greenberger-Horne-Zeilinger states of Rydberg atoms*

Abstract

The multipartite Greenberger–Horne–Zeilinger (GHZ) states play an important role in large-scale quantum information processing. We utilize the polychromatic driving fields and the engineered spontaneous emissions of Rydberg states to dissipatively drive three- and four-partite neutral atom systems into the steady GHZ states, at the presence of the next-nearest neighbor interaction of excited Rydberg states. Furthermore, the introduction of quantum Lyapunov control can help us optimize the dissipative dynamics of the system so as to shorten the convergence time of the target state, improve the robustness against the spontaneous radiations of the excited Rydberg states, and release the limiting condition for the strengths of the polychromatic driving fields. Under the feasible experimental conditions, the fidelities of three- and four-partite GHZ states can be stabilized at 99.24 % and 98.76 %, respectively.

Quantum logic and entanglement by neutral Rydberg atoms: methods and fidelity

“…Reference [312] Dissipation with asymmetric interactions (section 5.3.1) 9 9 .88%; Bell state; upper right of page 3 of reference [272] Reference [272] 99.91%; two-qubit entanglement; text below figure 2 on page 4 of reference [313] Reference [313] 99.47%; three-qubit entanglement; text below figure 4 on page 4 of reference [314] Reference [314] 99.09%; three-qubit entanglement (via cavity); lower left of page 1642 of reference [315] Reference [315] Dissipation (section 5.3.2) 99.9%; Bell state; figure 2 on page 3 of reference [316] Reference [316] 99%; Bell state (via cavity); text above figure 7 on page 5 of reference [317] Reference [317] 99.7%; two-qubit entanglement; end of section 4 on page 2300 of reference [318] Reference [318] 99.98%; two-qubit entanglement; text above figure 3 on page 10124 of reference [319] Reference [319] 98.24%; three-qubit entanglement (via cavity); lower left of page 5 of reference [320] Reference [320] 99%; six-qubit entanglement; upper right of page 4 of reference [321] Reference [321] 99.24%; three-qubit entanglement; abstract of reference [322] Reference [322] 98%; three-qubit entanglement; abstract of reference [323] Reference [323] Compensating Rydberg interactions by using oscillating Ω (section 5.4) 9 9 .35%; CNOT gate; middle left on page 4 of reference [147] Reference [147] 99.6%; C Z gate; text below equation (10) on page 1203 of reference [148] Reference [148] 98%; Bell state; figure 9(c) on page 8 of reference [149] Reference [149] 99%; C Z gate; lower left of page 7 of reference [150] (fast) b Reference [150] 99.1%; SWAP gate; texts below figure 3 and 4(a) on pp 816 and 817 of reference [240] Reference [240] a Most references show more than one type of gates or entanglement, where an operation with larger fidelity is quoted. b Here, 'fast' only means that they do not depend on Rydberg excitation with a Rabi frequency derived with a perturbation theory via the antiblockade, while a practical experimental implementation has a speed limited by experimentally feasible parameters.…”

“…Then, |D becomes the only stable state in the process of dissipation. Later on, it was found that by choosing appropriate detunings, interactions between the states, and dissipation, entanglement with various forms can be created, shown in references [318,[321][322][323]. Dissipation can also be used to generate entanglement with dipole-dipole flip-flop processes as shown in reference [319].…”

Light manipulation by dual channel storage in ultra-cold Rydberg medium

“…[14] The large interaction between Rydberg atoms will cause the dipoleblockade effect, which makes Rydberg-EIT medium exhibit enhanced optical nonlinearity. [15,16] Owing to this, Rydberg medium has emerged as a platform to realize quantum gate, [17][18][19][20] entanglement, [21][22][23][24][25] bound state, [26,27] and quantum devices, [28][29][30][31] including single-photon sources, switches, transistors, and absorbers. Recently, light propagation and storage in Rydberg-EIT medium [32][33][34][35][36][37][38] have been realized experimentally.…”

Realization of Deutsch–Jozsa Algorithm in Rydberg Atoms by Composite Nonadiabatic Holonomic Quantum Computation with Strong Robustness Against Systematic Errors

“…[70] To demonstrate the superiority of our idea, we focus on the robustness to the control errors by comparing three different schemes, that is, the single-loop NHQC, the composite NHQC and the dynamic counterpart in the execution of the DJ algorithm under the same condition. In fact, implementing the DJ algorithm with the dynamic method has been proposed in the Rydberg atom system [71] based on the Rydberg-Rydberg interaction [72][73][74][75][76][77][78][79][80][81][82][83][84][85][86][87][88][89][90][91] as well as in cavity QED system. [92] For clarity and for a concrete comparison, we consider the dynamic method in ref.…”