  It is known that eigenvalues of Zakharov-Shabat problem can be used to encode
a signal in soliton communication lines. We propose to use dispersion
oscillation fiber as a new versalite tool to control the eigenvalues. A fiber
with sine-wave variation of the core diameter can be used to manage both real
and imaginary parts of the eigenvalues. Change of real part of the eigenvalues
results in a splitting of an optical breather into two distinct pulses
propagating with the different group velocities. Change of imaginary parts of
the eigenvalues allows to realize a reverse process of merge of two solitons
into high-intensity pulse. The splitting of optical breather and merge of
solitons can be obtained even under the strong effect of stimulated Raman
scattering. We believe tools and techniques based on use of dispersion
oscillating fiber will grant unprecedented control over soliton eigenstates.
