High Light Tuning Efficiency in All Optical In₂Se₃ Coated Micro Knot Resonator Structure

In this paper, we demonstrate high light tuning efficiency in indium selenide (In2Se3) coated micro knot resonator (MKR). Tuning of output optical power is realized via externally pump light excitation at wavelengths of 405, 532 and 660 nm. High light tuning efficiency is achieved with improved coating method, enhanced light-matter interaction, strong absorption of In2Se3 and highly sensitive to change of the coupling condition. The tuning efficiency of the output optical power is up to 0.815 dB/mW. The temporal response of the structure is around 1.6 ms under 532-nm pump light excitation. The sensitivity depends on micro knot resonator resonance including Q factor and ER. The MKR tuning performance with various diameters of the resonator and the diameter of the microfiber is investigated. The advantages of this device are easy fabrication, all-optical tuning, high sensitivity and fast response. This proposed structure might find potential applications in all-fiber-optic based tunable devices such as optical modulator, detector, etc.