| Project/Area Number |
12650330
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
電子デバイス・機器工学
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| Research Institution | HOKKAIDO UNIVERSITY |
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Principal Investigator |
MISHIMA Teruhito Hokkaido Univ., Grad. School of Engin., Prof., 大学院・工学研究科, 教授 (30091507)
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| Co-Investigator(Kenkyū-buntansha) |
KOYANAGI Kojiro Hokkaido Univ., Grad. School of Engin., Inst., 大学院・工学研究科, 助手 (00001347)
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| Project Period (FY) |
2000 – 2001
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| Project Status |
Completed (Fiscal Year 2001)
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| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2001: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 2000: ¥2,000,000 (Direct Cost: ¥2,000,000)
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| Keywords | Orthogonally polarized pump FWM / Photorefractive effect / Optical signal distributor / OPPFWM / Time constant / Temporal response / Switching / Phase conjugation / 正・負キャリア / 位相共役光 / 回折効率 |
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| Research Abstract |
The temporal response is one of basic and important properties of optical signal distributor. The response of orthogonally polarized pump four wave mixing (OPPFWM) for optical signal distributor investigated intensively by this research :
In the first year (FY2000), we discovered some BaTiO_3 crystals exhibit an anomalous phenomena that the diffraction efficiency of OPPFWM distributor increases for a first few seconds of grating erasure period. We showed, through theoretical analysis and experiment, the phenomena happens when both negative and positive charge carriers with different time constants exist and primary charge carrier has longer time constant, comparing to secondary charge carrier.
In the second year (FY2001), we studied in the two cases : Primary and secondary gratings are in phase and they are totally out of phase. We showed in the out of phase case the grating erasure is much faster than the other. In addition to it, we proposed a novel way for switching the distributor by applying external electric field to the crystal and destroy the phase-matching of the four wave mixing, without erasing the gratings. By this way, it is possible that the switching time becomes shorter by several orders of magnitudes.
In conclusion, we have obtained useful results on basic properties of OPPFWM, especially on its temporal behavior for optical signal distributors.
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