Pilot study for z-polarization production by using coherent Cherenkov radiation in THz frequency region

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K13394
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: General applied physics
• Research Institution: Tohoku University
• Principal Investigator: Hama Hiroyuki 東北大学, 電子光理学研究センター, 教授 (70198795)
• Co-Investigator(Renkei-kenkyūsha): NANBU Ken-ichi 東北大学, 電子光理学研究センター, 技術専門職員 (00422072) ; TOHKOKU Chihiro 東北大学, 電子光理学研究センター, 技術一般職員 (20450190)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: z偏光 / チェレンコフ光 / コヒーレント放射

Outline of Final Research Achievements

Final goal of this research study is production of z-polarization light by using radially polarized Cherenkov radiation that is emitted from electrons passing through dielectric medium. We have established a linac scheme for production of very short electron pulses, such as ~80 femtosecond, to produce coherent radiation. In addition a specially designed mirror system to transport the ring shape Cherenkov light onto a detector located more than 10 m downstream was fabricated.
A computing code for radiation from moving charge has developed by ourselves and we found that the z-polarization state is unlikely to be produced by means of simple focusing process because spatial condition for interference in longer wavelength such as Terahertz region becomes lax.

Free Research Field

ビーム物理学