光纤光栅的温度增敏实验

用热膨胀系数较大的聚合物材料对光纤光栅进行封装处理,极大地提高了光纤光栅的温度灵敏度。我们将光纤光栅封装于两种不同的聚合物材料中,其温度灵敏度分别提高6倍和23倍之多。这是迄今有文献报道的最大的光纤光栅温度灵敏度。

TEMPERATURE SENSITIVITY ENHANCING EXPERIMENT OF FIBER BRAGG GRATINGS

Based on the (001) and (111) oriented valence band Luttinger Kohn Hamiltonian,we have discussed the band structures,densities of states (DOS),the optical matrix elements and gain property for these two kinds of quantum wells (QWs).Because of the anisotropy of the material structure,(111) QW has smaller in plane heavy hole effective mass,this property can benefit the lattice matched and compressively strained QW lasers.Although the (001) QW has smaller in plane light hole effective mass,the value is too close to that of the (111) QW.And the stronger mixing effect of the holes in (001) QW results in a much larger DOS,with the same carrier density,tensile (111) QW has a higher gain coefficient than its counterpart(001)QW.Thus the tensile (111) QW lasers may still have better device properties.We can say that the better characteristics of the lattice matched and compressively strained (111) QW lasers are resulted not only from the smaller in plane effective mass,but also from the weaker mixing effect of valence bands.