Quantum state manipulation via Raman coherence

Summary form only given. The study on the interaction between electromagnetic fields and multi-level atoms or molecules has discovered many interesting effects including electromagnetically induced transparency (EIT) enhanced dispersion with reduced absorption, and lasing without inversion. Recent interests include ultraslow group velocity of light, and superluminal light propagation. Atomic coherence created between different atomic levels plays an essential rule in these experiments. On the other hand, quantum features in the interaction between electromagnetic fields and three-level systems based on atomic coherence have attracted extensive theoretical interests. These include generation of amplitude-squeezed and quantum noise-correlated states of light with EIT, entanglement of atomic states with light fields, and quantum memory for light. According to these theoretical works, manipulation of quantum states of either light fields or atoms via atomic coherence is possible. We study quantum state manipulation of light via coherently driven Raman coherence in a /spl Lambda/-type three-level system of rubidium vapor under far off one-photon resonance condition both theoretically and experimentally.