title: Slow light Mach-Zehnder interferometer as label-free biosensor with scalable sensitivity.
abstract: The design, fabrication, and characterization of a label-free Mach-Zehnder interferometer (MZI) optical biosensor that incorporates a highly dispersive one-dimensional (1D) photonic crystal in one arm are presented. The sensitivity of this slow light MZI-based sensor scales with the length of the slow light photonic crystal region. The numerically simulated sensitivity of a MZI sensor with a 16 μm long slow light region is 115,000 rad/RIU-cm, which is sevenfold higher than traditional MZI biosensors with millimeter-length sensing regions. An experimental bulk refractive index detection sensitivity of 84,000 rad/RIU-cm is realized and nucleic acid detection is also demonstrated.
authors.forename: Kun
authors.initials: K
authors.lastname: Qin
authors.forename: Shuren
authors.initials: S
authors.lastname: Hu
authors.forename: Scott T
authors.initials: ST
authors.lastname: Retterer
authors.forename: Ivan I
authors.initials: II
authors.lastname: Kravchenko
authors.forename: Sharon M
authors.initials: SM
authors.lastname: Weiss
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D007368:Interferometry / Q000295:instrumentation*; D008027:Light; D057230:Limit of Detection; D012822:Silicon Dioxide
chemical_list: D012822:Silicon Dioxide