| 1. |
- Chen, Xi, et al.
(författare)
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Photothermal Switching of SOI Waveguide-Based Mach-Zehnder Interferometer with Integrated Plasmonic Nanoheater
- 2014
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Ingår i: Plasmonics. - : Springer. - 1557-1955 .- 1557-1963. ; 9:5, s. 1197-1205
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Tidskriftsartikel (refereegranskat)abstract
- We theoretically and numerically investigated the photothermal switching of a Mach-Zehnder interferometer (MZI) based on two Si waveguides integrated with plasmonic nanoheaters. The nanoheater is a composite nanowire with Au/Al2O3/Au three-layer structure, which is designed to have a highly efficient optical absorption peak at wavelength of 1,064 nm. Based on this finding, we further analyze a MZI built with two 40-μm-long symmetric waveguide branches, each integrated with a 20-μm-long nanoheater. The optical switching power of the MZI device is 190 mW (280 mW) for the capped (buried) channel waveguide, when pumped by a circular Gaussian beam with a waist of 10 μm. Alternatively, the switching power can be reduced to 38 mW (56 mW) by using an astigmatic Gaussian beam, with a semi-major axis of 10 μm and an aspect ratio of 5. The switching response time of the MZI is 0.7 μs (1.0 μs) for capped (buried) channel waveguide design. Our design opens a new route for optically driven non-contact optical on-off switching with sub-microsecond time response.
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| 2. |
- Chen, Xi, et al.
(författare)
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Photothermally tunable silicon-microring-based optical add-drop filter through integrated light absorber
- 2014
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Ingår i: Optics Express. - 1094-4087. ; 22:21, s. 25233-25241
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Tidskriftsartikel (refereegranskat)abstract
- An optically pumped thermo-optic (TO) silicon ring add-drop filter with fast thermal response is experimentally demonstrated. We propose that metal-insulator-metal (MIM) light absorber can be integrated into silicon TO devices, acting as a localized heat source which can be activated remotely by a pump beam. The MIM absorber design introduces less thermal capacity to the device, compared to conventional electrically-driven approaches. Experimentally, the absorber-integrated add-drop filter shows an optical response time of 13.7 mu s following the 10%-90% rule (equivalent to a exponential time constant of 5 mu s) and a wavelength shift over pump power of 60 pm/mW. The photothermally tunable add-drop filter may provide new perspectives for all-optical routing and switching in integrated Si photonic circuits.
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| 3. |
- Chen, Xi, et al.
(författare)
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Photothermally tunable silicon-microring-based optical add-drop filter through integrated light absorber
- 2014
-
Ingår i: Optics Express. - : Optica Publishing Group. - 1094-4087. ; 22:21, s. 25233-25241
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Tidskriftsartikel (refereegranskat)abstract
- An optically pumped thermo-optic (TO) silicon ring add-drop filter with fast thermal response is experimentally demonstrated. We propose that metal-insulator-metal (MIM) light absorber can be integrated into silicon TO devices, acting as a localized heat source which can be activated remotely by a pump beam. The MIM absorber design introduces less thermal capacity to the device, compared to conventional electrically-driven approaches. Experimentally, the absorber-integrated add-drop filter shows an optical response time of 13.7 μs following the 10%–90% rule (equivalent to a exponential time constant of 5 μs) and a wavelength shift over pump power of 60 pm/mW. The photothermally tunable add-drop filter may provide new perspectives for all-optical routing and switching in integrated Si photonic circuits.
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| 4. |
- Chen, Xi, et al.
(författare)
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Photothermally tunable silicon microring-resonator-based optical add-drop filter
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- A themro-optic (TO) silicon photonic add-drop filterwith small switching power and fast response is experimentallydemonstrated. We propose that metal-insulator-metal (MIM)absorbers can be integrated into the silicon TO devices, acting asan efficient and localized heat source. The MIM absorber designintroduces less thermal capacity to the device, comparing to theelectrically driven heater used in conventional TO devices. As a keyelement in silicon photonics, microring resonators have applicationin wavelength-division-multiplexing (WDM) devices, owning to theirunique spectrum properties. In this work, a silicon microring add-dropfilter is equipped with a MIM absorber. Experimentally, the deviceshows a measured optical response time of 5.0 μs and pumping powerderivative of the wavelength shift of 60 pm/mW.
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| 5. |
- Qiu, Min, et al.
(författare)
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Plasmonic enhanced photothermal effects and its applications
- 2014
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Konferensbidrag (refereegranskat)abstract
- We review here our recent studies on plasmonic enhanced photothermal effects in metallic nanostructure, and the applications of such effects. When light is shined on a prefect metamaterial absorber patterned with e-beam lithography, the gold nanoparticles (NPs) forming the absorber can be either transformed to nano-spherical-domes, or to truncated-octahedral shaped or multi-twined nanocrystals with large crystal grain sizes and flat boundary facets. The evolution of morphology and crystallinity of the gold NPs can be also observed. Evidences clearly show that the surface melting and the coalescence mechanism play a key role on nanocrystals formation. These melted gold nanospheres can even be transferred to another substrate, on which the transferred NPs exhibit excellent size uniformity. The strong photothermal effects can also be utilized to tune silicon photonics waveguides and resonators. It is shown that all-optical photothermal switching of Mach-Zehnder interferometers (MZI), silicon disk resonators, and silicon ring resonators is possible with the help of plasmonic nanoheaters. The switching response time and power consumption are all at reasonably low level.
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| 6. |
- Shi, Yuechun, et al.
(författare)
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All-optical switching of silicon disk resonator based on photothermal effect in metal-insulator-metal absorber
- 2014
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Ingår i: Optics Letters. - 0146-9592 .- 1539-4794. ; 39:15, s. 4431-4434
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Tidskriftsartikel (refereegranskat)abstract
- Efficient narrowband light absorption by a metal-insulator-metal (MIM) structure can lead to high-speed light-to-heat conversion at a micro-or nanoscale. Such a MIM structure can serve as a heater for achieving all-optical light control based on the thermo-optical (TO) effect. Here we experimentally fabricated and characterized a novel all-optical switch based on a silicon microdisk integrated with a MIM light absorber. Direct integration of the absorber on top of the microdisk reduces the thermal capacity of the whole device, leading to high-speed TO switching of the microdisk resonance. The measurement result exhibits a rise time of 2.0 mu s and a fall time of 2.6 mu s with switching power as low as 0.5 mW; the product of switching power and response time is only about 1.3 mW.mu s. Since no auxiliary elements are required for the heater, the switch is structurally compact, and its fabrication is rather easy. The device potentially can be deployed for new kinds of all-optical applications.
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| 7. |
- Shi, Yuechun, et al.
(författare)
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All-optical switching of silicon disk resonator based on photothermal effect in metal–insulator–metal absorber
- 2014
-
Ingår i: Optics Letters. - : Optica Publishing Group. - 0146-9592 .- 1539-4794. ; 39:15, s. 4431-4434
-
Tidskriftsartikel (refereegranskat)abstract
- Efficient narrowband light absorption by a metal–insulator–metal (MIM) structure can lead to high-speed light-to-heat conversion at a micro- or nanoscale. Such a MIM structure can serve as a heater for achieving all-optical light control based on the thermo-optical (TO) effect. Here we experimentally fabricated and characterized a novel all-optical switch based on a silicon microdisk integrated with a MIM light absorber. Direct integration of the absorber on top of the microdisk reduces the thermal capacity of the whole device, leading to high-speed TO switching of the microdisk resonance. The measurement result exhibits a rise time of 2.0 μs and a fall time of 2.6 μs with switching power as low as 0.5 mW; the product of switching power and response time is only about 1.3 mW·μs1.3 mW·μs. Since no auxiliary elements are required for the heater, the switch is structurally compact, and its fabrication is rather easy. The device potentially can be deployed for new kinds of all-optical applications.
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