Enhanced second-order nonlinear optical response of LiNbO3 films upon Er doping

Abstract

Erbium-doped LiNbO3 films have been produced in a single-step process by alternate pulsed laser deposition. The dopant is incorporated in submonolayers whose nominal indepth separation is varied in the range 1.7–4.0 nm to lead respectively to Er concentrations in the range 3.4–0.6×1020 atoms/cm−3. All the films exhibit the characteristic Er3+ photoluminescence at 1.54 μm with lifetime values as high as 3 ms. The d33 nonlinear coefficients determined from second-harmonic generation experiments are in the range 22–28 pm/V, the films having nominal Er submonolayer indepth separation of 3–4 nm exhibiting d33 values slightly above that of the bulk material. The comparison of the d33 values obtained in the Er-doped films to those reported earlier for similar undoped films shows clearly that both the structural quality and the second-harmonic performance of the films can be enhanced by Er doping.

Optical activation of Er3+ in Al2O3 during pulsed laser deposition

“…There is no evidence of segregation of Er to the surface, indicating that Er is effectively incorporated in the Al 2 O 3 structure. This is similar to what has been reported for Er incorporation in lithium niobate by PLD at temperatures up to 600°C [12]. The RBS analysis indicates that the Er areal density is similar for all the samples, the mean value being (4.7 ± 0.9) · 10 15 at.…”

Fabrication and Characteristics of Heavily Fe-Doped LiNbO3/Si Heterojunction

“…Except for the peak of the substrate, a stronger peak of LN:Fe 5 (006) at 39.1° was simultaneously measured. The full width half maximum (FWHM) of the (006) oriention of LN:Fe 5 is about 0.37°, which is less than the FWHM value (1.4°) of the undoped films of LN single crystal [17]. The results indicate c -axis oriented LN film with very few flaws was successfully deposited on the Si substrate.…”