Zn-4-Aminopyridine Coordination Compound as a Novel Saturable Absorber in Ho-Doped Fiber Laser System

Abstract

A coordination-based material, Zn-4-aminopyridine, is demonstrated for the first time as a nonlinear optical modulator for passive mode-locking operating at the extended 2 µm wavelength region. The coordination compound was deposited onto an arc-shaped fiber and subsequently incorporated into a ring-cavity laser configuration. Stable soliton pulses were achieved at a center wavelength of approximately 2078.06 nm, with a repetition rate of 15.11 MHz and a pulse duration of 1.70 ps. This work successfully introduces coordination compounds as a viable and versatile class of saturable absorbers for mode-locking in holmium-doped fiber lasers at extended 2 µm operation.