Ultra-Compact Short Pulse and Coherent Teraherts (THz) Light Source Using Super-radiance

2015 Fiscal Year Final Research Report

• Project/Area Number: 23226020
• Research Category: Grant-in-Aid for Scientific Research (S)
• Allocation Type: Single-year Grants
• Research Field: Applied physics, general
• Research Institution: High Energy Accelerator Research Organization
• Principal Investigator: Urakawa Junji 大学共同利用機関法人高エネルギー加速器研究機構, 研究支援戦略推進部, URA (00160333)
• Co-Investigator(Renkei-kenkyūsha): TERUNUMA Nobuhiro 高エネルギー加速器研究機構, 加速器研究施設, 教授 (70237014) ; HONDA Yousuke 高エネルギー加速器研究機構, 加速器研究施設, 助教 (40509783) ; SAKAUE KAZUYUKI 早稲田大学, 高等研究所, 助教 (80546333) ; Yamamoto Shigeru 高エネルギー加速器研究機構, 物質構造科学研究所, 教授 (20191405) ; Kashiwagi Shigeru 東北大学, 学内共同利用施設等, 准教授 (60329133) ; Yang Jinfeng 大阪大学, 産業科学研究所, 准教授 (90362631) ; WASHIO MASAKAZU 早稲田大学, 理工学術院, 教授 (70158608) ; KURIKI Masao 広島大学, 先端物質科学研究科, 教授 (80321537)
• Research Collaborator: FUKUDA Masafumi ; TAKATOMI Toshikazu ; Liu Shenggnuang 上海交通大学, 准教授 ; Deshpande Abhay SAMEER研究所, 研究員、主任研究員 ; Potylitsyn Alexander Tomsk Polytechnic University, 教授 ; Tishchenko Alexey A. National Research Nuclear University(MEPHI), 准教授 ; Konoplex Ivan. V. University of Oxford, Department of Physics, 講師 ; Ghosh Subhendu Inter University Accelerator Centre, 主任研究員
• Project Period (FY): 2011-04-01 – 2016-03-31
• Keywords: 高周波電子銃 / フェムト秒レーザー / フォトカソード / 高電界加速 / 自由電子レーザー

Outline of Final Research Achievements

Laser pulse energy of third harmonic generation of 800nm became 2.7mJ from 1.0mJ with 90 femtosec at gun cathode and the pulse was within 1.0% in regard to pointing and energy stability. After 90 fs electron single bunch and 4 micro-bunch train were generated and accelerated upto 8MeV, the characteristics of broadband and quasi-monochromatic radiation due to transition and Smith-Purcell radiation were measured. By tuning the micro-bunch spacing to the THz wavelength, it is possible to generate a narrowband coherent THz wave. Depending on whether an ideal Comb beam can be formed in the RF gun by high gradient acceleration, super-radiance peak power from the small wiggler (30cm) with five period reaches about 10MW peak power at 1pC/micro-bunch and about 100MW peak power at 10pC/micro-bunch. We confirmed the Super-radiation experimentally. Innovative THz light source applications can be developed soon through international cooperative network.

Free Research Field

加速器科学