Caldas Paulo, Rego Gaspar, Ivanov Oleg V, Santos José L
INESC Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal.
Appl Opt. 2010 Jun 1;49(16):2994-9. doi: 10.1364/AO.49.002994.
We present results on the characterization of the response of a dual resonance observed in the spectrum of a single long-period grating arc-induced in a B/Ge co-doped fiber to different physical parameters. The dual resonance is formed by two overlapping resonances corresponding to coupling of the core mode to symmetric and antisymmetric cladding modes. The behavior of the resonances is studied when the grating is subject to strain, bending, torsion, temperature, or external refractive-index changes. The strain, bending, and torsion sensitivities of the two resonances differ, whereas the temperature sensitivities are almost the same. The sensitivities to variation in external refractive index are the same for the two resonances when the long-period grating is straight and differ when the fiber with the grating is curved.
我们展示了关于在B/Ge共掺杂光纤中通过电弧诱导产生的单根长周期光栅光谱中观察到的双共振响应特性与不同物理参数之间关系的研究结果。该双共振由两个重叠的共振构成，分别对应纤芯模式与对称和反对称包层模式的耦合。当光栅受到应变、弯曲、扭转、温度或外部折射率变化影响时，我们研究了这些共振的行为。两种共振的应变、弯曲和扭转灵敏度不同，而温度灵敏度几乎相同。当长周期光栅为直线时，两种共振对外界折射率变化的灵敏度相同；当带有光栅的光纤弯曲时，两种共振对外界折射率变化的灵敏度则不同。
