title: Highly sensitive refractometer with a photonic-crystal-fiber long-period grating.
abstract: We present highly sensitive refractometers based on a long-period grating in a large-mode-area photonic crystal fiber (PCF). The maximum sensitivity is 1500 nm/refractive index unit at a refractive index of 1.33, to our knowledge the highest reported for any fiber grating. The minimal detectable index change is 2 x 10(-5). The high sensitivity is obtained by infiltrating the sample into the holes of the PCF to give a strong interaction between the sample and the probing field.
authors.affiliation: COM.DTU, Department of Communications, Optics and Materials, Technical University of Denmark, DK-2800 Kgs.Lyngby, Denmark. lars.rindorf@teknologisk.dk
authors.forename: Lars
authors.initials: L
authors.lastname: Rindorf
authors.forename: Ole
authors.initials: O
authors.lastname: Bang