title: Multicore fiber with integrated fiber Bragg gratings for background-free Raman sensing.
abstract: In the last years a variety of fiber optic Raman probes emerged, which are only partly suited for in vivo applications. The in vivo capability is often limited by the bulkiness of the probes. The size is associated with the required filtering of the probes, which is necessary due to Raman scattering inside the fibers. We employed in-line fiber Bragg gratings (FBG) as notch filter for the collection path and integrated them in a novel type of Raman probe. Multicore singlemode fibers (MCSMF) were designed and drawn integrating 19 singlemode cores to achieve better collection efficiency. A Raman probe was assembled with one excitation fiber and six MCSMF with inscribed FBGs as collection fibers. The probe was characterized regarding Raman background suppression, collection efficiency, and distance dependence. First Raman measurements on brain tissue are presented.
authors.affiliation: Institute of Photonic Technology Jena e.V., Albert-Einstein-Str. 9, 07745 Jena, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Dochow
authors.forename: Ines
authors.initials: I
authors.lastname: Latka
authors.forename: Martin
authors.initials: M
authors.lastname: Becker
authors.forename: Ron
authors.initials: R
authors.lastname: Spittel
authors.forename: Jens
authors.initials: J
authors.lastname: Kobelke
authors.forename: Kay
authors.initials: K
authors.lastname: Schuster
authors.forename: Albrecht
authors.initials: A
authors.lastname: Graf
authors.forename: Sven
authors.initials: S
authors.lastname: Brückner
authors.forename: Sonja
authors.initials: S
authors.lastname: Unger
authors.forename: Manfred
authors.initials: M
authors.lastname: Rothhardt
authors.forename: Benjamin
authors.initials: B
authors.lastname: Dietzek
authors.forename: Christoph
authors.initials: C
authors.lastname: Krafft
authors.forename: Jürgen
authors.initials: J
authors.lastname: Popp
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000295:instrumentation*; D057054:Molecular Imaging / Q000295:instrumentation*; D012031:Refractometry / Q000295:instrumentation*; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*; D013552:Swine; D018511:Systems Integration; D014159:Transducers