  Atomic response to a probe beam can be tailored, by creating coherences
between atomic levels with help of another beam. Changing parameters of the
control beam will change the nature of coherences and hence the nature of
atomic response as well. Such change can depend upon intensity of both probe
and control beams, in a nonlinear fashion. We present a situation where this
nonlinearity in dependence can be precisely controlled, as to obtain different
variations as desired. We also present a detailed analysis of how this
nonlinear dependency arises and show that this is an interesting effect of
several Coherent Population Trap(CPT) states that exist and a competition among
them to trap atomic population in them.
