Wavelength dispersion of Ti induced refractive index change in LiNbO₃as a function of diffusion parameters

Analysis of titanium concentration and refractive index profiles of Ti:LiNbO3 channel waveguide

“…The computed Ti-concentration profile of a Ti:LiNbO 3 planar waveguide along depth is plotted in Fig. 4 along with the experimental data of Fouchet et al [5]. The agreement is again reasonably good.…”

“…13 and compared with the available experimental data [5]. As shown in Table 1, the values of the surface Ti-concentration lie within ±7.5% of the experimental results.…”

“…Here, the values of α o and α e have been adjusted to fit the experimental data for the refractive index changes after the Ti-diffusion. Table 2 compares the experimental data obtained by Fouchet et al [5] for Z-cut substrate with the computed results taking α o = 0.5 and α e =0.8 at 0.6328 μm transmitting wavelength. The agreement is satisfactory.…”

“…These parameters are dependent on the diffusion temperature and, to some extent, on the ambient condition. We have taken C o =70.72 mass% for Z-cut LiNbO 3 substrate at 1050°C [5,6], and experimentally determined the D z and D x values. A titanium film of 950°A thick was deposited on the substrate by an electronbeam evaporation system and lithographically patterned to form metal strip of 6.3 μm width.…”

“…Comparison of the reported experimental data[5] with the computed values of surface refractive index change for Z-cut LiNbO 3Fig. 5 a Top-view of the fabricated Ti:LiNbO 3 waveguide by reflected light microscopy, b near-field image of the fabricated waveguide at 1.31 μm transmitting wavelength, (2 W=6.3 μm, τ= 95 nm, T=1050°C, t=6 h)…”