Transfer of amplitude and phase modulation to a different wavelength using coherently prepared sodium vapor

We present a scheme, based on coherent Raman scattering, to transfer the complete information content of an optical field from one spectral band to another with good efficiency, high fidelity, and large bandwidth. We demonstrate the transfer of both amplitude and phase modulation to new frequencies by scattering in a coherently prepared sodium vapor. The scattering process for this system has a bandwidth of at least tens of MHz and preserves the field envelope with a fidelity of 98%.