Project/Area Number |
13554004
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 展開研究 |
Research Field |
Astronomy
|
Research Institution | HOKKAIDO UNIVERSITY |
Principal Investigator |
BABA Naoshi Hokkaido Univ., Grad. School of Eng., Prof., 大学院・工学研究科, 教授 (70143261)
|
Co-Investigator(Kenkyū-buntansha) |
NISHIKAWA Jun National Astronomical Obs., Optical and Infrared Astron. Division, Inst., 光学赤外線天文学観測システム研究系, 助手 (70280568)
MIURA Noriaki Kitami Inst. of Tech., Faculty of Eng., Asso. Prof., 工学部, 助教授 (30209720)
ISHIGAKI Tsuyoshi Hokkaido Univ., Grad. School of Eng., Inst., 大学院・工学研究科, 助手 (40312384)
|
Project Period (FY) |
2001 – 2003
|
Project Status |
Completed (Fiscal Year 2003)
|
Budget Amount *help |
¥9,900,000 (Direct Cost: ¥9,900,000)
Fiscal Year 2003: ¥3,200,000 (Direct Cost: ¥3,200,000)
Fiscal Year 2002: ¥2,800,000 (Direct Cost: ¥2,800,000)
Fiscal Year 2001: ¥3,900,000 (Direct Cost: ¥3,900,000)
|
Keywords | Stellar interferometer / Extrasolar planet / Nulling interferometer / Geometric phase / Pancharatnam phase / ヌル干渉計 |
Research Abstract |
To directly detect extrasolar planets nulling interferometer gains wide attention, where extremely bright star-light is destructively interfered. In the first experiments, one linearly polarized light beam is considered as the synthesis of two orthogonal linearly polarized light and these decomposed polarization components are destructively interfered by use of a polarizes. However, this situation does not fully simulate a practical pulling interferometer. In the next experiments two separate beams are generated with a Mach-Zehnder interferometer and geometric phase modulation is exerted in each arm so as to perform pulling interference. Geometric phase or Pancharatnam phase is independent of wavelength in nature and the phase shift value is adjustable. These characteristics of geometric phase are very useful for pulling interferometer with multi-element telescopes. Experimental results reveal the feasibility of separate phase modulation of an arbitrary amount of radians (less than 2π) in pulling interferometer and the extinction ratio of 0.8x10^4 is achieved.
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