title: The role of group index engineering in series-connected photonic crystal microcavities for high density sensor microarrays.
abstract: We experimentally demonstrate an efficient and robust method for series connection of photonic crystal microcavities that are coupled to photonic crystal waveguides in the slow light transmission regime. We demonstrate that group index taper engineering provides excellent optical impedance matching between the input and output strip waveguides and the photonic crystal waveguide, a nearly flat transmission over the entire guided mode spectrum and clear multi-resonance peaks corresponding to individual microcavities that are connected in series. Series connected photonic crystal microcavities are further multiplexed in parallel using cascaded multimode interference power splitters to generate a high density silicon nanophotonic microarray comprising 64 photonic crystal microcavity sensors, all of which are interrogated simultaneously at the same instant of time.
authors.affiliation: Department of Electrical and Computer Engineering, Microelectronics Research Center, University of Texas at Austin , 10100 Burnet Rd., Austin, Texas 78758, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zou
authors.affiliation: Omega Optics, Inc. , 8500 Shoal Creek Blvd., Austin, Texas 78757, USA.
authors.forename: Swapnajit
authors.initials: S
authors.lastname: Chakravarty
authors.affiliation: Department of Electrical and Computer Engineering, Microelectronics Research Center, University of Texas at Austin , 10100 Burnet Rd., Austin, Texas 78758, USA.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Department of Electrical and Computer Engineering, Microelectronics Research Center, University of Texas at Austin , 10100 Burnet Rd., Austin, Texas 78758, USA.
authors.forename: Ray T
authors.initials: RT
authors.lastname: Chen