Title :
Optical-Damage-Resistant Ti-Diffused LiNbO3 Strip Waveguide Doped With Scandium
Author :
De-Long Zhang ; Cong-Xian Qiu ; Wing-Han Wong ; Dao-Yin Yu ; Pun, Edwin Yue-Bun
Author_Institution :
Sch. of Precision Instrum. & Opto-Electron. Eng., Tianjin Univ., Tianjin, China
Abstract :
We report Sc3+-doped Ti:LiNbO3 (Ti:Sc:LN) strip waveguide fabricated by Ti-diffusion following homogeneous Sc3+-diffusion-doping in a Z-cut congruent substrate. We show that Sc3+-doping has little contribution to the substrate index and the Li2O out-diffusion was effectively suppressed. The refractive index increases in the waveguide layer are mainly contributed from the Ti4+ dopants. The waveguide well supports both transverse electric (TE) and magnetic (TM) modes, is single-mode at 1.5-μm wavelength, and has a loss of 1.4 dB/cm for the TE mode and 1.8 dB/cm for the TM mode. A secondary ion mass spectrometry study shows that the Sc3+-profile covers 80% ordinary refractive index profile and almost 100% extraordinary refractive index profile, and the 1/e Sc3+ concentration is above the threshold of photorefractive effect. Further, two-beam hologram recording experimental results verify the optical-damage-resistant feature of the waveguide. Highlights are given for fabrication of an optical-damage-resistant Ti:Sc:LN waveguide.
Keywords :
lithium compounds; optical fabrication; optical testing; optical waveguides; photorefractive effect; photorefractive materials; refractive index; scandium; secondary ion mass spectra; titanium; (LiNbO3:Ti):Sc3+; 1/e Sc3+ concentration; Li2O out-diffusion; Sc3+-doped Ti:LiNbO3 strip waveguide; TE mode; TM mode; Ti-diffusion; Ti4+ dopants; Z-cut congruent substrate; extraordinary refractive index profile; homogeneous Sc3+-diffusion-doping; loss 1.4 dB; loss 1.8 dB; optical-damage-resistant Ti-diffused LiNbO3 strip waveguide; optical-damage-resistant Ti:Sc:LN waveguide fabrication; photorefractive effect; scandium; secondary ion mass spectrometry; single-mode wavelength; substrate index; transverse electric mode; transverse magnetic mode; two-beam hologram recording; waveguide layer; waveguide well; wavelength 1.5 mum; Nonlinear optics; Optical device fabrication; Optical refraction; Optical surface waves; Optical variables control; Optical waveguides; Surface waves; Sc3+ diffusion-doping; Ti:Sc:LiNbO3 strip waveguide; photorefractive effect;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2014.2335893
