Two waveguide layers in lithium niobate crystal formed by swift heavy Kr ion irradiation*
Liu Taoa),b), Huang Qingc), Zhao Jin-Huad), Kong Wei-Jina),b), Liu Penge), Zhang Liane), Zhou Yu-Fane), Yu Xiao-Feie), Wang Leie), Wang Xue-Line)†
       
(a) The microscope image of the polished end facet of the swift Kr-ion irradiated LN sample; (b) image of the near-field intensity image at the wavelength of 633 nm; (c)image of the near-field intensity profile of the TE-polarized fundamental guide mode at the end of the ion track collected with the CCD at 633 nm.