Long period grating in ZBLAN fiber using the <i>pull-and-heat</i> method

This Letter demonstrates a method for long-period grating inscription in fluoride fibers using the <i>pull-and-heat</i> method. It also presents an analysis of fiber deformation when subjected to a combination of heating temperature, duration, and tension and suggests a methodology for high-precision micro-tapering fiber regions developing for low-loss LPG inscription. Finally, we show that the proposed methodology has the potential for even stronger LPGs, since it offers a high degree of uniformity between the periods and controllability of the micro-tapering regions to meet the optical requirements of the components in a wide range of applications.