Summary form only given. Presents a one-step process for the fabrication of efficient, compact long-period gratings. The technique makes use ofa controlled arc to periodically modify an optical fiber by a pair of electrodes. The setup comprises a commercially available splicer whose fiber holding mechanism is replaced by a motorized stage, which allows the translation of the fiber between the electrodes. The motion of the fiber and the input current to the electrodes is controlled by a computer and an optical spectrum analyzer constantly monitors the transmission spectrum of the grating being fabricated.