  We propose a new scheme for realizing nonlocal nondegenerate optical
parametric amplifier by means of genuine four-mode entanglement. The
nondegenerate optical parametric amplifier is regarded as a unitary
transformation from two input fields to two outputs. Two inputs and two outputs
are located at the remote stations respectively. Employing off-line four-mode
entanglement, homodyne detection, classical communication and local
displacement, the nonlocal nondegenerate optical parametric amplifier can be
achieved. This scheme can be implemented with a setup that is experimentally
accessible at present.
