Application of optical micro-fibres decorated with a co-doped Er3+/Yb3+ silica film with fast desorption response for environmental cleanliness measurement of a laser facility

•An airbourne molecular contaminants sensor is developed.•The sensor is based on optical micro/nanofibers with a fast desorption function.•The fast desorption function is achieved by doping rare earth in the functional layer.•The devices meet the practical requirements for cleanliness measurement of a laser facility. Airbourne molecular contaminants (AMCs)11AMC: airbourne molecular contaminants; OMNF: optical micro/nano-fiber; GC–MS: gas chromatography-mass spectrometry; FOA: final optics assemblies; SEM: scanning electron microscopy; DFB: distributed feedback laser; EDS: energy dispersive spectrometer; WDM: wavelength division multiplexing; DBP: dibutyl phthalate; DEP: diethyl phthalate; DOP: dioctyl phthalate. are critical for improving laser performance. In this study, we demonstrate an AMC sensor based on optical micro/nano-fibres (OMNFs) decorated with a co-doped silica film with a fast desorption function. The shapes and diameters of the OMNFs can be precisely controlled using a homemade nano/sub-micron, ultra-fine optical waveguide precision fabrication system. The sensing performance of the as-fabricated devices was evaluated, and a maximum resolution of 7.48 μg/m3 and a sensitivity of 0.5347 dB/(mg/m3) were obtained for devices with a diameter of 2.0 μm. By adjusting the concentration of Er3+/Yb3+, an excellent photo-thermal effect can be achieved to realize fast AMC desorption responses. The experimental results revealed that heating desorption can shorten the desorption time to 1/40 of that of free desorption. The proposed device is expected to be applied extensively in high-performance low/ultra-low-temperature gas sensing, photothermal modulation, and air-flow speed sensing applications.