Oxford University Press eBooks

Seeing light in subtle ways

S. Haroche, J. M. Raimond

Published Aug 10, 2006• 0 citations

Abstract

This chapter describes two cavity quantum electrodynamics (CQED) studies guided by the spirit of thought experiments. The first one is a direct implementation of the recoiling slit interferometer imagined by Bohr. Section 6.1 discusses a closely related experiment, in which a Ramsey interferometer is used instead of the unrealistic Young's one proposed by Bohr. The second experiment, described in Section 6.2, realizes another dream of early quantum mechanics by achieving a non-destructive detection of a single photon. Section 6.3 shows that the quantum non-demolition (QND) measurement of a single photon by a Rydberg atom corresponds to the operation of a control-not quantum gate in which the photon is the control bit and the atom the target. Section 6.4 discusses the extension of the atom-field manipulations to larger fields, based on the dispersive atom-cavity interaction. Section 6.5 describes an alternative statistical method, also based on the atom-field dispersive interaction. The method relies on the preliminary translation of the field in phase space by controlled complex amplitudes.

DOI: 10.1093/acprof:oso/9780198509141.003.0006

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