ATOMIC COHERENCE INITIATED NOISE FREE-ENERGY TRANSFER IN A RESONANT MEDIUM

Energy transfer from pump to probe in a resonant medium is accompanied by the addition of spontaneous noise of the medium. A scheme is presented where this energy transfer can be made noise free i.e., a coherent signal is transformed into a coherent signal with larger intensity. The scheme uses a LAMBDA-system with injected coherence between two ground levels - this coherence leads to the transfer of energy from the pump to the probe beam.