Limits...
Fast generations of tree-type three-dimensional entanglement via Lewis-Riesenfeld invariants and transitionless quantum driving

View Article: PubMed Central - PubMed

ABSTRACT

Recently, a novel three-dimensional entangled state called tree-type entanglement, which is likely to have applications for improving quantum communication security, was prepared via adiabatic passage by Song et al. Here we propose two schemes for fast generating tree-type three-dimensional entanglement among three spatially separated atoms via shortcuts to adiabatic passage. With the help of quantum Zeno dynamics, two kinds of different but equivalent methods, Lewis-Riesenfeld invariants and transitionless quantum driving, are applied to construct shortcuts to adiabatic passage. The comparisons between the two methods are discussed. The strict numerical simulations show that the tree-type three-dimensional entangled states can be fast prepared with quite high fidelities and the two schemes are both robust against the variations in the parameters, atomic spontaneous emissions and the cavity-fiber photon leakages.

No MeSH data available.


(a) The schematic setup for generating tree-type three-dimensional entanglement; (b) the level configurations and relevant transitions. (c) The APF design of the schematic setup for TQD to fast generate tree-type three-dimensional entanglement.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC5036061&req=5

f1: (a) The schematic setup for generating tree-type three-dimensional entanglement; (b) the level configurations and relevant transitions. (c) The APF design of the schematic setup for TQD to fast generate tree-type three-dimensional entanglement.

Mentions: The schematic setup for generating the tree-type three-dimensional entanglement is shown in Fig. 1(a). Three atoms are trapped respectively in three spatially separated optical cavities which are connected by two fibers. Under the short fiber limit (lv)/(2πc) ≤ 1, only the resonant modes of the fibers interact with the cavity modes55, where l is the length of the fiber and v is the decay rate of the cavity field into a continuum of fiber modes. The atomic level configurations and relevant transitions are shown in Fig. 1(b). As shown in Fig. 1(b), the five-level atom1 and atom3 are both M-type with two excited states /eL〉 and /eR〉 and three ground states /gL〉, /g0〉 and /gR〉. The four-level atom2 is tripod-type with one excited state /e0〉 and three ground states /gL〉, /g0〉 and /gR〉. The atomic transition (j = 1, 3) is resonantly coupled to the left-circularly (right-circularly) polarized mode of jth cavity with corresponding coupling constant gj,L(R), and is resonantly coupled to the left-circularly (right-circularly) polarized mode of cavity2 with corresponding coupling constant g2,L(R)). The transitions and are resonantly driven by classical laser fields with the time-dependent Rabi frequencies Ωj(t) and Ω2(t), respectively. Then the whole system can be dominated by the interaction Hamiltonian (ħ = 1):


Fast generations of tree-type three-dimensional entanglement via Lewis-Riesenfeld invariants and transitionless quantum driving
(a) The schematic setup for generating tree-type three-dimensional entanglement; (b) the level configurations and relevant transitions. (c) The APF design of the schematic setup for TQD to fast generate tree-type three-dimensional entanglement.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5036061&req=5

f1: (a) The schematic setup for generating tree-type three-dimensional entanglement; (b) the level configurations and relevant transitions. (c) The APF design of the schematic setup for TQD to fast generate tree-type three-dimensional entanglement.
Mentions: The schematic setup for generating the tree-type three-dimensional entanglement is shown in Fig. 1(a). Three atoms are trapped respectively in three spatially separated optical cavities which are connected by two fibers. Under the short fiber limit (lv)/(2πc) ≤ 1, only the resonant modes of the fibers interact with the cavity modes55, where l is the length of the fiber and v is the decay rate of the cavity field into a continuum of fiber modes. The atomic level configurations and relevant transitions are shown in Fig. 1(b). As shown in Fig. 1(b), the five-level atom1 and atom3 are both M-type with two excited states /eL〉 and /eR〉 and three ground states /gL〉, /g0〉 and /gR〉. The four-level atom2 is tripod-type with one excited state /e0〉 and three ground states /gL〉, /g0〉 and /gR〉. The atomic transition (j = 1, 3) is resonantly coupled to the left-circularly (right-circularly) polarized mode of jth cavity with corresponding coupling constant gj,L(R), and is resonantly coupled to the left-circularly (right-circularly) polarized mode of cavity2 with corresponding coupling constant g2,L(R)). The transitions and are resonantly driven by classical laser fields with the time-dependent Rabi frequencies Ωj(t) and Ω2(t), respectively. Then the whole system can be dominated by the interaction Hamiltonian (ħ = 1):

View Article: PubMed Central - PubMed

ABSTRACT

Recently, a novel three-dimensional entangled state called tree-type entanglement, which is likely to have applications for improving quantum communication security, was prepared via adiabatic passage by Song et al. Here we propose two schemes for fast generating tree-type three-dimensional entanglement among three spatially separated atoms via shortcuts to adiabatic passage. With the help of quantum Zeno dynamics, two kinds of different but equivalent methods, Lewis-Riesenfeld invariants and transitionless quantum driving, are applied to construct shortcuts to adiabatic passage. The comparisons between the two methods are discussed. The strict numerical simulations show that the tree-type three-dimensional entangled states can be fast prepared with quite high fidelities and the two schemes are both robust against the variations in the parameters, atomic spontaneous emissions and the cavity-fiber photon leakages.

No MeSH data available.