  Quantum Zeno and anti-Zeno effects are studied in an asymmetric nonlinear
optical coupler composed of a probe waveguide and a system waveguide. The
system is a nonlinear waveguide operating under non-degenerate hyper-Raman
process, while both the pump modes in the system are constantly interacting
with the probe waveguide. The effect of the presence of probe on the temporal
evolution of the system in terms of the number of photons in Stokes and
anti-Stokes modes as well as phonon number is quantified as Zeno parameter. The
negative (positive) values of the Zeno parameter in the specific mode are
considered as the signatures of the quantum Zeno (anti-Zeno)effect in that mode
of the system. It is observed that the phase mismatch in Stokes and anti-Stokes
generation processes can be controlled to induce a transition between quantum
Zeno and anti-Zeno effects for both off-resonant and resonant hyper-Raman
process. However, in case of off-resonant hyper-Raman process in the system
waveguide, the frequency detuning parameters can also be used analogously to
cause the desired crossover. Further, the general nature of the physical system
and the perturbative technique used here allowed us to analytically study the
possibilities of observing quantum Zeno and anti-Zeno effects in a large number
of special cases, including situations where the process is spontaneous,
partially spontaneous and/or the system is operated under degenerate
hyper-Raman process, or a simple Raman process.
