Sensitivity of holey fiber based sensors

We analyze the mechanisms contributing to the overall sensitivity of optical sensors based on holey fibers. For this purpose we investigate the shift of the Bragg-matched wavelength in a sensor with a Bragg grating as well as the change of birefringence in a polarimetric sensor. For the sake of simplicity we concentrate on the response of the sensor to temperature. We show that the change of refractive index of silica is not always the dominating source of the sensor's response.