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arXiv · 0709.1335

Interference of Spontaneous Emission of Light from two Solid-State Atomic Ensembles

M. Afzelius·M. U. Staudt·H. de. Riedmatten·C. Simon·S. R. Hastings-Simon·R. Ricken·H. Suche·W. Sohler·N. Gisin
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Abstract

We report an interference experiment of spontaneous emission of light from two distant solid-state ensembles of atoms that are coherently excited by a short laser pulse. The ensembles are Erbium ions doped into two LiNbO3 crystals with channel waveguides, which are placed in the two arms of a Mach-Zehnder interferometer. The light that is spontaneously emitted after the excitation pulse shows first-order interference. By a strong collective enhancement of the emission, the atoms behave as ideal two-level quantum systems and no which-path information is left in the atomic ensembles after emission of a photon. This results in a high fringe visibility of 95%, which implies that the observed spontaneous emission is highly coherent.

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M. Afzelius, M. U. Staudt, H. de. Riedmatten, C. Simon, S. R. Hastings-Simon, R. Ricken, H. Suche, W. Sohler, N. Gisin. 2007-11-23. Interference of Spontaneous Emission of Light from two Solid-State Atomic Ensembles. https://doi.org/10.1088/1367-2630%2F9%2F11%2F413

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