为了寻求高质量和高密度的密集波分复用器件,采用了在双掺铟铁的铌酸锂晶体中透射式记录/正交式读出方案制作体全息光栅的方法,对体全息光栅衍射特性进行理论分析和实验验证。利用波长为532nm的激光记录尺寸比为1:1的体全息光栅,然后用中心波长为1550nm的红外通讯波长成功读出,取得了波长选择性为0.5nm的波长衍射特性数据。同时,利用2维耦合波理论的闭形式解析解得到了该体全息光栅衍射效率随波长的变化关系。结果表明,实验结果与理论预期相符合,这一方法对制作体全息光栅密集波分复用器件的实用化是有帮助的。

In order to obtain good quality and high-dense wavelength division multiplexing (DWDM) devices,the diffraction property of volume holographic gratings,produced in an iron and indium co-doped LiNbO3 crystal by means of the transmission writing and orthogonal readout (TWOR) scheme,was analyzed theoretically and verified experimentally.The volume holographic grating with a grating size ratio of 1:1 was recorded at the laser wavelength of 532nm,and was successfully read out by using a tunable laser at the central wavelength around 1550nm.Correspondingly,the wavelength selectivity of 0.5nm was achieved,which was measured as the 3dB bandwidth of the diffraction efficiency curve.Meanwhile,the relationship of diffraction efficiency versus reading wavelength for such a volume holographic grating was obtained with the corrected solution to the 2-D coupled-wave equation in closed mathematical form.The experimental results agreed with the theoretical prediction well,and they show that the presented method is helpful for making a practical holographic grating DWDM device.