Conversion of spectral characteristics of laser radiation in periodic domain structures written by the electron-beam method in planar waveguides formed by Ti diffusion in Y-oriented LiNbO3

• Published in: Quantum electronics (Woodbury, N.Y.) N.Y.), 2018-09, Vol.48 (8), p.761-766
• Main Authors: Shandarov, S.M., Kokhanchik, L.S., Volk, T.R., Savchenkov, E.N., Borodin, M.V.
• Format: Article
• Language: English
• Subjects: Conversion; diffusion planar waveguide; Domains; Electron beams; Laser beams; lithium niobate; Lithium niobates; Microscopy; periodic domain structures; Phase matching; Planar waveguides; Plates (structural members); Refractivity; Second harmonic generation; SHG microscopy; waveguide quasi-phase-matching SHG
• ISSN: 1063-7818; 1468-4799
• DOI: 10.1070/QEL16710

Periodic domain structures for nonlinear conversion of spectral characteristics of laser radiation in the planar Ti : LiNbO3 waveguide have been formed by the method of electron-beam writing. Domain gratings with a spatial period of 6.50 μm formed in the Y-cut plate over a wide range of accelerating voltages have been visualised by the method of second harmonic generation microscopy (SHG-microscopy) in transmitting geometry and at waveguide excitation. It is found that the domain structure written at an accelerating voltage of 10 kV in a waveguide with an exponential refractive index profile and an effective thickness of 1.75 μm is characterised by high homogeneity. It is composed of continuous domain rows and provides near-quasi-phase-matching radiation conversion at a wavelength of 1053 nm into the second harmonic for the TE0 → TE1 waveguide process.