All-fiber setup for temperature sensing based on a polymeric-core PCF with semiconductor nanocrystals

Microstructured optical fibers present unique properties that enable a number of novel applications. This is due to their particular geometry, which includes an array of holes that runs along their axis, parallel to the core. The possibility of inserting nanoparticles in this type of fiber, especially in photonic crystal fibers, gives rise to novel applications in several areas. In particular, the insertion of luminescent semiconductor nanocrystals has been studied for temperature sensing applications. In this work, we present the development of an all-fiber optical circuit that is able to excite CdSe/ZnS nanocrystals, as well as to efficiently collect their emission, via a double-clad fiber. The nanocrystals were suspended in a polymer, which was inserted into the hollow core of a PCF. Two versions of this setup are discussed and have the advantage of being robust, simple, and of not requiring free-space optics. As a next step, the setup will be tested as a temperature sensor based on the monitoring of the luminescence spectrum.