In vacuo measurement of the sensitivity limit of planar bragg sensors

We present the direct measurement and modeling of the sensitivity limit of an integrated refractive index sensor for the detection of molecular monolayers. Direct UV writing can be used to fabricate a wide range of integrated optical devices particularly Bragg gratings. These Bragg gratings are inherently sensitive to temperature and strain. By etching a portion of the cladding, the mode within the grating region can be exposed to an analyte (Figure 1.a). The spectral response of the grating provides information about the refractive index of the analyte [1].