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arXiv:quant-ph/0208029 · Journal of Optics B Quantum and Semiclassical Optics

Optimized phase switching using a single-atom nonlinearity

Holger Friedrich Hofmann, Kunihiro Kojima, Shigeki Takeuchi, Keiji Sasaki

Published Apr 16, 2003• 108 citations
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Abstract

We show that a nonlinear phase shift of π can be obtained by using a single two-level atom in a one-sided cavity with negligible losses. This result implies that the use of a one-sided cavity can significantly improve the π/18 phase shift previously observed by Turchette et al (1995 Phys. Rev. Lett. 75 4710).
DOI
10.1088/1464-4266/5/3/304

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We investigate the single-mode operation of a quantum optical nonlinear $\ensuremath{\pi}$ phase-shift gate implemented by a single two-level atom in one-dimensional free space. Since the single-mode property of the input photons at the atom is not preserved in the interaction at the atom, we analyze the efficiency of single-mode operation that can still be achieved. We show how the input pulse shape can be optimized to obtain high efficiencies for the nonlinear single-mode operation. With this analysis, we obtain an optimal single-mode transmittance per photon of 78% for the successful nonlinear $\ensuremath{\pi}$ phase-shift operation.
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