Fiber optic hydrogen sulfide gas sensor utilizing surface plasmon resonance of Cu/ZnO thin films

摘要

We report a surface plasmon resonance based fiber optic hydrogen sulphide gas sensor using Cu/ZnO thin films. The sensor works on wavelength modulation scheme. The fiber optic probe was fabricated by removing the cladding of appropriate length from the fiber and depositing copper and ZnO thin films on the unclad core by thermal evaporation technique. The presence of hydrogen sulphide gas around the probe changes the dielectric function of zinc oxide and a dip is observed in transmitted spectrum. With the increase in the gas concentration shift in the resonance wavelength has been observed. The proposed sensor can be used for online monitoring and remote sensing of hydrogen sulphide gas in the environment.