Atomic layer deposition of zirconium oxide thin film on an optical fiber for cladding light strippers

Abstract

Cladding light strippers are essential components in high-power fiber lasers used for removal of unwantedcladding light that can distort the beam quality or even damage the whole fiber laser system. In this study, an AtomicLayer Deposition system was used for the first time to prepare the cladding light stripper devices using a 40 nm thickzirconia layer grown on optical fiber. The thickness of the zirconia coating was confirmed using the Scanning ElectronMicroscopy (SEM) and the Ellipsometry techniques. The elemental analysis was also performed using the wavelengthdispersive X-ray spectroscopy technique. The Raman spectroscopy and XRD data confirm the structure of the atomiclayer deposition-grown zirconia thin films to be predominantly amorphous. The cladding light stripper devices formedusing the zirconia thin films with the lengths of 8.5 and 15.5 cm were able to strip approximately 30% (~1.5 dB) and40% (~2.3 dB) of the unwanted cladding light.