Abstract :
Oxygen ions with energies of 6.0 or 3.0 MeV were implanted into y-cut Yb:YCOB crystals at fluences ranging from 5.0 1013 to
2.0 1015 ions/cm2 at room temperature, forming optical planar waveguide structures. Dark-mode line spectroscopy was applied at two
wavelengths, 633 and 1539 nm, in various excitation configurations, showing strong enhancement of one of the indices (nx) in the implanted near
surface. The nx refractive index profile is reconstructed by a reflectivity calculation method and compared to the ion energy losses profiles deduced
from SRIM-code simulation. Moreover, the near-field patterns were imaged by an end-fire coupling arrangement
