Low-loss, geometry-invariant optical waveguides with near-zero-index materials

Optical materials with nearly zero refractive indices have driven emerging applications ranging from geometry-invariant optical tunneling, nonlinear optics, optical cloaking to thermal emission manipulation. In conventional dielectric photonic circuits, light scattering and back reflection at the wa...

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Main Authors: Wang Danqing, Dong Kaichen, Li Jingang, Grigoropoulos Costas, Yao Jie, Hong Jin, Wu Junqiao
Format: Article
Language:English
Published: De Gruyter 2022-11-01
Series:Nanophotonics
Subjects:
Online Access:https://doi.org/10.1515/nanoph-2022-0445
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author Wang Danqing
Dong Kaichen
Li Jingang
Grigoropoulos Costas
Yao Jie
Hong Jin
Wu Junqiao
author_facet Wang Danqing
Dong Kaichen
Li Jingang
Grigoropoulos Costas
Yao Jie
Hong Jin
Wu Junqiao
author_sort Wang Danqing
collection DOAJ
description Optical materials with nearly zero refractive indices have driven emerging applications ranging from geometry-invariant optical tunneling, nonlinear optics, optical cloaking to thermal emission manipulation. In conventional dielectric photonic circuits, light scattering and back reflection at the waveguide bends and crossings leads to significant optical loss. Here we propose to use near-zero-index materials as a cladding layer for low-loss optical waveguides, where optical modes are tightly confined within the dielectric core region. Compared to conventional waveguides, the near-zero-index waveguides are superior in maintaining a high mode-filling factor for small device sizes close to the diffraction limit and reducing the crosstalk in between at a sub-wavelength separation. In addition, we found that light propagation is robust to waveguide bends in a small radius (∼µm) and geometry variation in the cross section. Hollow waveguides with near-zero-index cladding layers further support low-loss light propagation because materials absorption is minimized from the air core. Our work offers critical insights into future designs of low-loss and miniaturized photonic devices.
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institution Kabale University
issn 2192-8614
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publishDate 2022-11-01
publisher De Gruyter
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series Nanophotonics
spelling doaj-art-ec04fcdb42ad47b3ad01fd4aa07c3fe32024-11-25T11:19:08ZengDe GruyterNanophotonics2192-86142022-11-0111214747475310.1515/nanoph-2022-0445Low-loss, geometry-invariant optical waveguides with near-zero-index materialsWang Danqing0Dong Kaichen1Li Jingang2Grigoropoulos Costas3Yao Jie4Hong Jin5Wu Junqiao6Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA, 94720, USADepartment of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA, 94720, USADepartment of Mechanical Engineering, University of California, Berkeley, Berkeley, CA, 94720, USADepartment of Mechanical Engineering, University of California, Berkeley, Berkeley, CA, 94720, USADepartment of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA, 94720, USALightgration LLC, Saratoga, CA, 95070, USADepartment of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA, 94720, USAOptical materials with nearly zero refractive indices have driven emerging applications ranging from geometry-invariant optical tunneling, nonlinear optics, optical cloaking to thermal emission manipulation. In conventional dielectric photonic circuits, light scattering and back reflection at the waveguide bends and crossings leads to significant optical loss. Here we propose to use near-zero-index materials as a cladding layer for low-loss optical waveguides, where optical modes are tightly confined within the dielectric core region. Compared to conventional waveguides, the near-zero-index waveguides are superior in maintaining a high mode-filling factor for small device sizes close to the diffraction limit and reducing the crosstalk in between at a sub-wavelength separation. In addition, we found that light propagation is robust to waveguide bends in a small radius (∼µm) and geometry variation in the cross section. Hollow waveguides with near-zero-index cladding layers further support low-loss light propagation because materials absorption is minimized from the air core. Our work offers critical insights into future designs of low-loss and miniaturized photonic devices.https://doi.org/10.1515/nanoph-2022-0445crosstalkdiffraction limitgeometry invariancelight scatteringoptical waveguideszero index
spellingShingle Wang Danqing
Dong Kaichen
Li Jingang
Grigoropoulos Costas
Yao Jie
Hong Jin
Wu Junqiao
Low-loss, geometry-invariant optical waveguides with near-zero-index materials
Nanophotonics
crosstalk
diffraction limit
geometry invariance
light scattering
optical waveguides
zero index
title Low-loss, geometry-invariant optical waveguides with near-zero-index materials
title_full Low-loss, geometry-invariant optical waveguides with near-zero-index materials
title_fullStr Low-loss, geometry-invariant optical waveguides with near-zero-index materials
title_full_unstemmed Low-loss, geometry-invariant optical waveguides with near-zero-index materials
title_short Low-loss, geometry-invariant optical waveguides with near-zero-index materials
title_sort low loss geometry invariant optical waveguides with near zero index materials
topic crosstalk
diffraction limit
geometry invariance
light scattering
optical waveguides
zero index
url https://doi.org/10.1515/nanoph-2022-0445
work_keys_str_mv AT wangdanqing lowlossgeometryinvariantopticalwaveguideswithnearzeroindexmaterials
AT dongkaichen lowlossgeometryinvariantopticalwaveguideswithnearzeroindexmaterials
AT lijingang lowlossgeometryinvariantopticalwaveguideswithnearzeroindexmaterials
AT grigoropouloscostas lowlossgeometryinvariantopticalwaveguideswithnearzeroindexmaterials
AT yaojie lowlossgeometryinvariantopticalwaveguideswithnearzeroindexmaterials
AT hongjin lowlossgeometryinvariantopticalwaveguideswithnearzeroindexmaterials
AT wujunqiao lowlossgeometryinvariantopticalwaveguideswithnearzeroindexmaterials