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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:
; ;  [1];  [2]
  1. Department of Electrical and Computer Engineering, Microelectronics Research Center, University of Texas at Austin, 10100 Burnet Rd., Austin, Texas 78758 (United States)
  2. Omega Optics, Inc., 8500 Shoal Creek Blvd., Austin, Texas 78757 (United States)
Publication Date:
OSTI Identifier:
22261574
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 14; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CRYSTALS; DENSITY; LIGHT TRANSMISSION; RESONANCE; SENSORS; WAVEGUIDES

Citation Formats

Zou, Yi, E-mail: yzou@utexas.edu, Zhu, Liang, Chen, Ray T., E-mail: raychen@uts.cc.utexas.edu, and Chakravarty, Swapnajit, E-mail: swapnajit.chakravarty@omegaoptics.com. The role of group index engineering in series-connected photonic crystal microcavities for high density sensor microarrays. United States: N. p., 2014. Web. doi:10.1063/1.4871012.
Zou, Yi, E-mail: yzou@utexas.edu, Zhu, Liang, Chen, Ray T., E-mail: raychen@uts.cc.utexas.edu, & Chakravarty, Swapnajit, E-mail: swapnajit.chakravarty@omegaoptics.com. The role of group index engineering in series-connected photonic crystal microcavities for high density sensor microarrays. United States. doi:10.1063/1.4871012.
Zou, Yi, E-mail: yzou@utexas.edu, Zhu, Liang, Chen, Ray T., E-mail: raychen@uts.cc.utexas.edu, and Chakravarty, Swapnajit, E-mail: swapnajit.chakravarty@omegaoptics.com. 2014. "The role of group index engineering in series-connected photonic crystal microcavities for high density sensor microarrays". United States. doi:10.1063/1.4871012.
@article{osti_22261574,
title = {The role of group index engineering in series-connected photonic crystal microcavities for high density sensor microarrays},
author = {Zou, Yi, E-mail: yzou@utexas.edu and Zhu, Liang and Chen, Ray T., E-mail: raychen@uts.cc.utexas.edu and Chakravarty, Swapnajit, E-mail: swapnajit.chakravarty@omegaoptics.com},
abstractNote = {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.},
doi = {10.1063/1.4871012},
journal = {Applied Physics Letters},
number = 14,
volume = 104,
place = {United States},
year = 2014,
month = 4
}
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