Controllable photoinduced optical attenuation in a single-mode optical fiber by irradiation of a femtosecond pulse laser

Abstract

Novel optical attenuation fibers were fabricated by the irradiation of a focused infrared femtosecond pulsed laser onto the core of a silica glass single-mode optical fiber. Optical attenuation at a wavelength of 1.55 microm proportionally increased with increasing numbers of irradiation points and was controllable under laser irradiation conditions. The single-mode property of the waveguide and the mode-field diameter of the optical fiber were maintained after irradiation of the femtosecond laser. It is suggested that the attenuation results from optical scattering at photoinduced spots formed inside the fiber core.

Femtosecond laser-induced microfeatures in glasses and their applications

“…Photo-induced optical attenuations in the optical fibers were observed after the irradiation of femtosecond pulse laser [42]. Fig.…”

Femtosecond pulse written fiber gratings: a new avenue to integrated fiber technology

“…Within the telecommunication range (1.5 μm), intracore microvoid FBGs show very low insertion losses. However, strong losses occur for light in the visible due to Mie scattering [130,131]. On the other hand, the large modifications by low-NA inscription can seriously compromise the guiding performance of the fiber, which leads to radiation mode coupling.…”

“…Especially for LPGs, where long sections are modified, high insertion losses are reported [43,61,64]. This may not always be unwanted, e. g. for the realization of in-fiber attenuators [130].…”

Eccentric core single‐mode fiber optical attenuator

“…All‐fiber fixed optical attenuators have advantages of simple structure and compatibility to the optical fiber communication systems, and they are easily packaged. Several techniques have been reported for implementation of these devices, such as metal‐ion‐doped fiber attenuator [2, 3], photoinduced optical attenuator in a single‐mode fiber (SMF) by irradiation of a femtosecond pulse laser [4] and photonic crystal fiber (PCF) optical attenuator [5]. However, the metal‐ion‐doped fiber is intrinsically accompanied by temperature elevation owing to their optical absorption nature, which is an undesirable phenomenon in recent high‐power optical networks [4].…”