2018 Fiscal Year Annual Research Report
On-chip modulation of optical signals using plasmonic induced phase transitions for realizing all-optical circuitry
| Project/Area Number |
17K18867
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| Research Institution | The University of Tokyo |
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Principal Investigator |
J・J Delaunay 東京大学, 大学院工学系研究科(工学部), 准教授 (80376516)
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| Co-Investigator(Kenkyū-buntansha) |
松井 裕章 東京大学, 大学院工学系研究科(工学部), 准教授 (80397752)
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| Project Period (FY) |
2017-06-30 – 2019-03-31
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| Keywords | 全光スイッチ / 光デバイス / プラズモニクス / ナノ材料 |
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| Outline of Annual Research Achievements |
Our research goal is to modulate light (signal) using light (control) in an integrated on-chip device with reduced footprint and energy consumption. In order to achieve this high-speed modulation of an optical signal by optical means, we have built an optical setup (pump-probe) that can record the response of a material to a light pulse with a resolution of approximately 100 femtoseconds, fabricated samples made of highly correlated metal-oxide materials such as VO2 in the forms of thin films, nanostructures, and plasmonic nanostructures, and characterized the samples using the developed optical setup. We have found a large and fast modulation in the light signal when the samples were exposed to a pulse of light. The fast modulation is of the order of several hundreds of femtoseconds, but it is unfortunately followed by a slower recovery of the order of hundreds of picoseconds. To clarify the origin of these different time responses, the response of the samples was investigated as a function of the power of the light pulse and the optical setup was modified to allow for a re-pump of the samples. We found that the standard mechanism reported in the literature involving an optically induced insulator-metal transition cannot explain our results. Finally, different strategies to reduce the slow recovery component have been tested. These recent results have been submitted, and our publication is under review.
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Research Products
(6 results)
