Atomic level structures for the present scheme

Figure 3. Atomic level structures for the present scheme. (a) Three-level atom for the atomic mode a, which is in the Raman resonance with the field reservoirs b_{1, 2}. (b) Two-level atom for the atomic reservoir N₁, which is coupled to the cavity mode c and the field reservoir b₁ through dispersive resonance. (c) Three-level atom for the atomic reservoir N₂, which is in the dispersive resonance with the cavity mode c and the field reservoir b₂.

Abstract

We show that it is possible to use an atom–cavity reservoir to prepare the two-mode squeezed and entangled states of a hybrid system of an atomic ensemble and an optical field, which do not directly interact with each other. The essential mechanism is based on the combined effect of a two-mode squeezing interaction and a beam–splitter interaction between the system and the reservoir. The reservoir mechanism is important for quantum networking in that it allows an interface between a localized matter-based memory and an optical carrier of quantum information without direct interaction.