Second-order interference effects in the spontaneous emission by two identical two-level atoms, separated a distance apart and both initially excited, are considered. On the basis of the analysis in our previous paper published in 2004, within fourth-order perturbation, detailed analysis of the second-order quantum interference in the emitted field is made. The interference arises both from single-photon states and two-photon states owing to interferences between different decaying sequences. By detailed analysis we have found some cancellations between single-photon and two-photon interference terms, and an interpretation of this is given. The contributions from the single- and the two-photon states as well as the total interference are analysed numerically for various interatomic distances and times. The contribution from a two-photon state is mostly larger than that from a single-photon state except when the atomic electric dipole is large, in which case the two contributions can be comparable. It is shown that the emission patterns from the two interacting atoms provide more information on atom–atom correlations than the decay time evolution of the atomic states population does. The number of interference fringes and the distance between them depend on the interatomic distance in a similar fashion to Young's interference fringes.Second-order interference effects in the spontaneous emission by two identical two-level atoms, separated a distance apart and both initially excited, are considered. On the basis of the analysis in our previous paper published in 2004, within fourth-order perturbation, detailed analysis of the second-order quantum interference in the emitted field is made. The interference arises both from single-photon states and two-photon states owing to interferences between different decaying sequences. By detailed analysis we have found some cancellations between single-photon and two-photon interference terms, and an interpretation of this is given. The contributions from the single- and the two-photon states as well as the total interference are analysed numerically for various interatomic distances and times. The contribution from a two-photon state is mostly larger than that from a single-photon state except when the atomic electric dipole is large, in which case the two contributions can be comparable. It is shown that the emission patterns from the two interacting atoms provide more information on atom–atom correlations than the decay time evolution of the atomic states population does. The number of interference fringes and the distance between them depend on the interatomic distance in a similar fashion to Young's interference fringes.

Journal of Modern OpticsFeb 21, 20062 citations

Entangling Distant Atoms by Interference of Polarized Photons

Xun‐Li Feng, Zhi‐Ming Zhang, Xiang-Dong Li +2 more

We propose a scheme to generate the entangled state of two Lambda-type three-level atoms trapped in distant cavities by using interference of polarized photons. Two possible spontaneous emission channels of each excited atom result in a coherent superposition of the states of two atoms. The subsequent detection of the different polarized photons reveals that both atoms are in different ground states, but an interference effect prevents us from distinguishing which atom is in which ground state; the atoms are thus entangled. In comparison with the original proposal of interference-induced entanglement [C. Cabrillo, J. Cirac, P. Garcia-Fernandez, and P. Zoller, Phys. Rev. A 59, 1025 (1999)]], in our scheme the weakly driven condition is not required, and the influence of atomic excitement and atomic recoil on the entanglement fidelity can be eliminated.We propose a scheme to generate the entangled state of two Lambda-type three-level atoms trapped in distant cavities by using interference of polarized photons. Two possible spontaneous emission channels of each excited atom result in a coherent superposition of the states of two atoms. The subsequent detection of the different polarized photons reveals that both atoms are in different ground states, but an interference effect prevents us from distinguishing which atom is in which ground state; the atoms are thus entangled. In comparison with the original proposal of interference-induced entanglement [C. Cabrillo, J. Cirac, P. Garcia-Fernandez, and P. Zoller, Phys. Rev. A 59, 1025 (1999)]], in our scheme the weakly driven condition is not required, and the influence of atomic excitement and atomic recoil on the entanglement fidelity can be eliminated.

Physical Review LettersMay 28, 2003227 citations

Quantum interference

Robert B. Griffiths

Cambridge University Press eBooksNov 29, 20010 citations

Double-slit interference with ultracold metastable neon atoms

Fujio Shimizu, Kazuko Shimizu, Hiroshi Takuma

A double-slit interference of ultracold neon atoms in the 1 ${\mathit{s}}_{3}$ metastable state is studied. The interferometer is aligned vertically, and because of gravity acceleration the atom changes its velocity as much as 2 m/s during the passage of the interference. The interference fringes are observed for the initial atomic velocity between 0 and 2 m/s.A double-slit interference of ultracold neon atoms in the 1${\mathit{s}}_{3}$ metastable state is studied. The interferometer is aligned vertically, and because of gravity acceleration the atom changes its velocity as much as 2 m/s during the passage of the interference. The interference fringes are observed for the initial atomic velocity between 0 and 2 m/s.

Physical Review AJul 1, 1992129 citations

Quantum Interference

David S. Simon

Undergraduate texts in physicsJan 1, 20250 citations

A double-slit interference of ultracold neon atoms in the 1

{\mathit{s}}_{3}

metastable state is studied. The interferometer is aligned vertically, and because of gravity acceleration the atom changes its velocity as much as 2 m/s during the passage of the interference. The interference fringes are observed for the initial atomic velocity between 0 and 2 m/s.