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Title: Genetically designed L3 photonic crystal nanocavities with measured quality factor exceeding one million

Abstract

We report on the experimental realization of ultra-high quality factor (Q) designs of the L3-type photonic crystal nanocavity. Based on genetic optimization of the positions of few nearby holes, our design drastically improves the performance of the conventional L3 as experimentally confirmed by direct measurement of Q ≃ 2 × 10{sup 6} in a silicon-based photonic crystal membrane. Our devices rank among the highest Q/V ratios ever reported in photonic crystal cavities, holding great promise for the realization of integrated photonic platforms based on ultra-high-Q resonators.

Authors:
;  [1]; ; ; ;  [2]; ;  [3]
  1. Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627 (United States)
  2. Dipartimento di Fisica, Università di Pavia, via Bassi 6, 27100 Pavia (Italy)
  3. Laboratory of Theoretical Physics of Nanosystems, Ecole Polytechnique Federale de Lausanne EPFL, CH-1015 Lausanne (Switzerland)
Publication Date:
OSTI Identifier:
22299872
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 24; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; CAVITIES; CRYSTALS; EV RANGE; MEMBRANES; NANOSTRUCTURES; OPTIMIZATION; QUALITY FACTOR; RESONATORS; SILICON

Citation Formats

Lai, Y., Badolato, A., E-mail: antonio.badolato@gmail.com, Pirotta, S., Urbinati, G., Gerace, D., Galli, M., Minkov, M., and Savona, V.. Genetically designed L3 photonic crystal nanocavities with measured quality factor exceeding one million. United States: N. p., 2014. Web. doi:10.1063/1.4882860.
Lai, Y., Badolato, A., E-mail: antonio.badolato@gmail.com, Pirotta, S., Urbinati, G., Gerace, D., Galli, M., Minkov, M., & Savona, V.. Genetically designed L3 photonic crystal nanocavities with measured quality factor exceeding one million. United States. doi:10.1063/1.4882860.
Lai, Y., Badolato, A., E-mail: antonio.badolato@gmail.com, Pirotta, S., Urbinati, G., Gerace, D., Galli, M., Minkov, M., and Savona, V.. Mon . "Genetically designed L3 photonic crystal nanocavities with measured quality factor exceeding one million". United States. doi:10.1063/1.4882860.
@article{osti_22299872,
title = {Genetically designed L3 photonic crystal nanocavities with measured quality factor exceeding one million},
author = {Lai, Y. and Badolato, A., E-mail: antonio.badolato@gmail.com and Pirotta, S. and Urbinati, G. and Gerace, D. and Galli, M. and Minkov, M. and Savona, V.},
abstractNote = {We report on the experimental realization of ultra-high quality factor (Q) designs of the L3-type photonic crystal nanocavity. Based on genetic optimization of the positions of few nearby holes, our design drastically improves the performance of the conventional L3 as experimentally confirmed by direct measurement of Q ≃ 2 × 10{sup 6} in a silicon-based photonic crystal membrane. Our devices rank among the highest Q/V ratios ever reported in photonic crystal cavities, holding great promise for the realization of integrated photonic platforms based on ultra-high-Q resonators.},
doi = {10.1063/1.4882860},
journal = {Applied Physics Letters},
number = 24,
volume = 104,
place = {United States},
year = {Mon Jun 16 00:00:00 EDT 2014},
month = {Mon Jun 16 00:00:00 EDT 2014}
}
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  • Photonic crystal nanocavities are fabricated in silicon membranes covered by thermally annealed silicon-rich nitride films with Erbium-doped silicon nanocrystals. Silicon nitride films were deposited by sputtering on top of silicon on insulator wafers. The nanocavities were carefully designed in order to enhance emission from the nanocrystal sensitized Erbium at the 1540 nm wavelength. Experimentally measured quality factors of {approx}6000 were found to be consistent theoretical predictions. The Purcell factor of 1.4 was estimated from the observed 20-fold enhancement of Erbium luminescence.
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