Experimental study of saturable and reverse saturable absorption of Zn nanoparticles photodeposited onto etched optical fibers

Abstract

In this paper, the non-linear optical response of photodeposited zinc nanoparticles onto an etched optical fiber is reported. Through chemical etching, 20 mm of the cladding of a standard single-mode optical fiber was removed to expose its core and subsequently, photodeposit zinc nanoparticles on it at different times (1, 5 and 10 min) by using a continuous wave laser at 1550 nm. The non-linear optical response was obtained by the P-scan technique using a high-gain pulsed amplifier with a pulse duration of 10 ns at a wavelength of 1550 nm. The experimental results showed that it is possible to get the effects of reverse saturable absorption (RSA) at irradiances less than 380 MW/cm 2 and saturable absorption (SA) for higher values. Consequently, the analysis of the results obtained shows that the third-order non-linear susceptibility x3 of the RSA is 2.2130 × 10−06 (esu) for 10 min of photodeposition, which decreases for shorter photodeposition times; On the other hand, the third-order non-linear susceptibility x3 of the SA is −5.8955 × 10−07 (esu) for 10 min of photodeposition, which increases for shorter exposure times. Finally, the experimental results obtained show that it is possible to make a photonic device with desired non-linear absorption properties by the photodeposition of metallic nanoparticles onto etched fibers, which makes it ideal for applications in optical communications.