Study On Fiber Devices Based On SPR And Multi-cladding Fiber

With the development of informational society,the informational society based on traditional electronic technology will turn to the photo-informational society.The all fiber system become more and more important,resulting of that it is necessary to investigate the fiber devices with the characteristics of compact structure,easy integration and excellent performance.Surface Plasmons(SPs)breaks through the limit of traditional optical diffraction and provides a method of light processing with nano-sized.Moreover,the multi-cladding fiber(MCF)devices with flexible sizes and various performances can be obtained by designing specially.It provides more possibility for obtaining the fiber devices with good performance,compact structure and easy integration by combining SPs with MCF.It is well applied in the fields of optical communication and optical sensing.In this paper,the basic characteristics of fiber surface palsmon reaonance(SPR)and MCF,and its applications in the fields of polarized filter and single-/double-parameter sensor are theoretical,simulative and experimental researched.The main research contents and innovative results as follow:1.An orthogonal double-side polished MCF SPR double-wavelength polarized filter is studied;moreover,experimental fabricate the important component of such polarized filter,which is the orthogonal double-side polished fiber.In theoretically,the polarized filtering at any wavelength would be obtained by optimizing the paremeters of structure.Accoding to the investigations,when the refractive index(RI)of dielectric is 1.47,the thinckness of dielectric in x-and y-polarization are 0.482?m,1.82 ?m and 1.117 ?m,1.82 ?m,respectively,the double-wavelength polarized filter at the wavelength of 980 nm/1550 nm and 1310 nm/1550 nm are designed,respectively.When the length of such device is 550 ?m,the largest bandwidth of polarized filtering at the wavelength of 1550 nm can reach at 400 nm.2.The single-and double-paremeter sensor of few mode-single mode-few mode(FSF)fiber structure based on few mode double-cladding fiber are experimentally fabricated.The influences of structural parameters on the transmission spectrum of sensor are analyzed.Moreover,the sensing characteristics of FSF fiber sensor is compared with single-and double-paremeter fiber SPR sensor.3.A D-shaped side-hole double cladding fiber SPR temperature sensor is proposed.The influence of the thickness of metal of SPR,the distance between the D-shaped hole and fiber core are investigated.When the RI of filled liquid is lower than the RI of cladding,the loss spectrum of sensor moves to shorter wavelength linearly with the increasing of temperature.Moreover,its temperature sensitivity can be up to-3.635 nm/?.4.A side-hole fiber SPR magnetic field sensor is provised.The influence of the thickness of metal of SPR,the distance between the side-hole and fiber core are investigated.When the magnetic fluid is full filled in the side-hole and the intensity of magnetic field is from 30 Oe to 210.9 Oe,the loss spectrum of such sensor shifts to the longer wavelength linearly.Moreover,the magnetic field sensitivity of side-hole fiber SPR magnetic field sensor is 1.063 nm/Oe.5.The orthogonal double-side polished fiber SPR sensor with the simultaneous measurement of RI and temperature,and side-hole fiber SPR sensor with the simultaneous measurement of magnetic field and temperature are provided.The characteristic of SPR is changed by using different kinds of metal or dielectric,which can be applied in detecting two physical quantities with high sensitivity.The length of the above sensors is millimeter.Moreover,the problems of normal sensor that the signal light is easily affected by environment and the structure is large,is solved.