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with measurements of thermo-optical properties of long period Bragg gratings. The variation of dn(T,lambda)/dT with fiber structure depends on the modal overlap of with each part of the fiber. Differences from one fiber structure to another will be subtle because the different glasses used and the resulting variation in overlap are, themselves, subtle. So, you might end up being able to use the numbers from this article. Another source of information is here: https://www.pmoptics.com/Glass_Temperature_Coefficient.html, giving a quadratic model (in temperature) along with dependence upon material and even pressure. These two sources give a good starting point.

Fiber bragg ve optik sensörler ince, hassas yapılara sahip olduğu için lamda ve sıcaklık kırıcılık indisi önemli bir yere sahiptir. Bu sensörler malzemenin yapısına bağlı olarak değişir.

Kırlma indisi de kuantum mekaniğinde olduğu gibi farklı enerji seviyelerine sahiptir