  We propose an efficient scheme for the generation of tunable optical
waveguide based on atomic vapor in N -type configuration. We exploit both
control field induced transparency and Kerr field induced absorption to produce
a flexible probe transparency window otherwise not feasible. We employ a
suitable spatial profile of control and Kerr beams to create a high contrast
refractive in- dex modulation that holds the key to guiding a weak narrow probe
beam. Further we numerically demonstrate that high contrast tunable waveguide
permits the propagation of different modes of probe beam to several Rayleigh
lengths without diffraction. This efficient guiding of narrow opti- cal beam
may have important applications in large density image processing, and high
resolution imaging.
