Introduction to IT Projects (Industrial Free Electron Laser and Its Applications)

Keywords Used For WWW Search:

High-Intensity Electron Beam Accelerator, Undulator, Optical Resonator, Free Electron Laser (FEL) Transport System, Industrial Free Electron Laser, Wide-Range Variable-Wavelength Laser from IR to UV Region, Very Short-Pulse High-Output Laser with Ultra sonic Effect, Application Technologies of Free Electron Laser, Organic Ablation, Super High-Speed Optical Modulation, Stable Isotope Separation.

Project Name:

Research and Development of Industrial Free Electron Laser and Its Applications

Country of Origin and Current Location:

Free Electron Laser Research Institute, Inc.

• Mailing address: 2-9-5 TsudaYamate, Hirakata, Osaka 573-0128, Japan
  

Project Coordinator:

Free Electron Laser Research Institute, Inc.

• Name: Akio Nagai
  
• Position: Center Manager
  
• Mailing address: 2-9-5 TsudaYamate, Hirakata, Osaka 573-0128, Japan
  
• Phone: +81-720-96-0414
  
• FAX: +81-720-96-0421
  
• E-mail: nagai@feli.co.jp
  

Brief Overall Project Summary:

The object of our research is to design and develop an industrial free electron laser (FEL), as well as to investigate various applications for which the laser may be employed. As part of the research and development process for the free electron laser (FEL), we have developed a number of underlying technologies and devices. These include: a high-intensity electron accelerator and electron beam transport system, a high accuracy wiggler, a high-immunity optical resonator, and finally, an FEL transport system. Using these technologies and devices, we have succeeded in achieving laser excitation in the IR, visible, and UV regions of the spectrum. As part of our ongoing research and development, we are working on new optical quantum processing technologies that make use of the variable wavelength properties of the free electron laser--these include laser ablation, and super high-speed optical modulation within a semiconductor's super-lattice structure.

Research and Development System:

FELI, established in March, 1991, is an R&D company operated with capital supplied by The Japan Key Technology Center and private companies. Research is expected to conclude by the end of March 1997.

This system is intended to promote experimental research on fundamental technologies in private sector, with The Japan Key Technology Center(70 %) and participating private companies (30 %) financing the capital requiring for this purpose.

Project Objectives:

The main objective of this research is to develop a high-power, high-efficiency, free electron laser (FEL) with a variable wavelength covering the IR, visible, and UV regions of the spectrum, and its applications. We also aim to develop new optical quantum processing technologies using this laser by making the best use of its variable wavelength properties.

Expected / Actual Results:

We could achieve the following world-top research results during the 30-month period since the beginning of the FEL facility construction:

1. Development of a high-brilliance electron injector
   We achieved a 10 times higher brilliance than conventional performance with our development of a stable-operating, hot-cathode electron gun which contributed to the success of FEL lasing.

2. Development of a long-pulse-duration, highly stable, RF source
   We developed a long-pulse-duration, highly-stable RF source with a variance of no more than 0.08 % for 24 ƒÊs (conventional performance is in the approximate range of 1 % for 5ƒÊs). This development enabled us to achieve accelerator output of 165 MeV, with a peak current of 40A, a minimum pulse-duration of 10 ps, and maximum pulse-duration of 24ƒÊs. This indeed constitutes very-short-pulse, high-power accelerator performance as not in the past.

3. Achievement of Lasing on 2 FEL equipment covering a spectral range from IR to visible region in just an 12-month period since development of the equipment
   We successfully achieved FEL lasing on 2 undulating-optical systems based on the above fundamental developments. In particular, we achieved lasing covering the spectral range from 0.63ƒÊm (visible red) to 20ƒÊm (IR), including high harmonic lasing. This lasing was achieved on 2 equipment within only 12 months of development--a world record--this represents a considerable shortening of the several-year development period that has been previously required to date elsewhere in the world.

4. Achievement of high-speed and variable-wavelength (tunability)
   The development of a high-accuracy undulator enabled us to continuously tune the resonant wavelength by remote control. Accordingly, we were thereby able to achieve a doubling in the resonant wavelength within a few seconds.

5. Discovery and confirmation of optimal wavelength by polishing and surface hardening of decayed teeth
   We confirmed the polishing and surface hardening effects of irradiating FEL ablation using a wavelength of 9.4ƒÊm on extracted teeth. We discovered that the surface of the teeth were hardened by means of increased crystallization of hydroxyapatite.

6. Completion of the 8th world FEL user's facility
   We, at FELI, can be proud of our achievements in completing the 8th FEL users facility in the world. The first such facility was constructed at Stanford University in 1977, where at that time, they succeeded in FEL lasing with a 3.4ƒÊm wavelength. Since then, over 50 FEL research facilities have been constructed, spanning the spectral range from submillimicron wavelengths to the short wavelength region. Of these 50 facilities, only 8 of them are open to users as follows: 5 in the U.S.A., namely Stanford University, University of California at Santa Barbara, the National Institute of Los Alamos, Vanderbilt University and Duke University. (These 5 facilities in the U.S.A. were given a huge financial boost by the American Strategic Defence Initiative (SDI) project advocated by former President Reagan, with a total budget amounting to some 300 billion yen.) The other 3 open facilities (one in each country) are located in: the Netherlands (FOM), France (LURE), and Japan (FELI)--see Table 1.

• Anticipated future achievements:

1. World's first FEL utility with broad wavelength tunability covering the FIR, IR, Visible, and UV regions of the spectrum.
   As shown in Table 1, there are 7 other facilities around the world accessible to users, and most of them are capable of covering only the IR to FIR portions of the spectrum. Ours is the only facility that covers the FIR, IR, visible, and UV regions of the spectrum.
   Table 1. List of FEL Users Facilities

   Research Organization	Electron Accelerator	Electron Gun	First Lasing (Year of Building)	FEL Wavelength Range (ƒÊm)	Peak Power (Average Power)	Research Theme
   Stanford Univ (USA)	Superconductive Linea Accelerator 66MeV, 5.6A	Hot Cathode	1977	3 - 15 20 - 60	1.2MW (1W)	solid state physics Solid state physics, bioscience, medicine
   UCSB (USA)	Van de Greaf 6MeV	Hot Cathode	1985	350 - 2500 60 - 350 30 - 90	( - 10kW)	Semiconductor solid state
   Duke Univ. (USA)(Mark III)	Normal Conductive Linea Accelerator 45MeV, 40A	Hot Cathode RF Gun	1986	1.8 - 9.5	2MW (3W)	Solid state physics
   Vanderbilt Univ. (USA)(Mark III)	Normal Conductive Linea Accelerator 45MeV, 40A	Hot Cathode RF Gun	1991 (1987)	2 - 8	3MW (6W)	Bioscience, medicine, solid state physics Solid state physics
   FOM FELIX (Netherlands)	Normal Conductive Linea Accelerator 45MeV, 70A	Hot Cathode	1991	5 - 30 16 - 110	5MW (0.5W)	Nuclear/ molecular physics, bioscience, medicine
   LURE CLIO (France)	Normal Conductive Linea Accelerator 70MeV, 75A	Hot Cathode	1992	1.8 - 17.5	10MW (9W)	Solid state physics
   LANL AFEL (USA)	Normal Conductive Linea Accelerator 15MeV, 100A	Optical Cathode	1993	4 - 6	10MW (1.5W)	Medical applications
   FELI (Japan)	Normal Conductive Linea Accelerator 33MeV, 42A 75MeV, 50A 160MeV, 60A 20MeV, 40A 20MeV, 40A	Hot Cathode	(1993) 1994 1995 1995 1996 1996	5 - 22 1 - 6 0.23 - 1.2 20 - 60 50 - 100	5MW (2W) 15MW(3W) 10MW(2W) 5MW(1W) 5 MW(1W)	Semiconductor solid state, isotope separation Medical applications Bioscience New material Catalyst development

2. Development of a method for simultaneous FEL beam sharing
   Since laser beams are generally highly-coherent, the splitting and distribution of laser beams are commonly achieved via the reflection / transmission properties of a beam splitter. However, this is unsuitable for simultaneous sharing of variable wavelength laser light, such as that produced by the FEL, due to the fact that reflectivity is dependent on the wavelength.

   We are developing a wavelength-independent method for the simultaneous sharing of FEL beams. The FEL beams pass through the 1 mm diameter exit hole in the output mirror which forms a part of the optical resonator in the free electron laser device. These FEL beams broaden by diffraction are transported to nearby experimental stations over a distance of several tens of meters; the beam radius involved is on the order of several centimeters. The simultaneous FEL beam sharing method we developed uses a series of specially-shaped fan-shaped mirrors (installed in each stations) to split and distribute the beams into roughly triangular, fan-shaped pieces. These mirrors are positioned such that the reflected beams do not overlap, and therefore interfere with each other. In this manner, as multiple sites may use FEL simultaneously, the rate of FEL use would be improved.

3. First lasing of the world's shortest wavelength FEL
   At present, the world's shortest wavelength of FEL produced by means of electron linac is 0.37ƒÊm--this was achieved by the National Institute of Los Alamos in 1993. We succeeded in short wavelength emission of 0.35ƒÊm with Undulator 3 using a 155-MeV electron beam in December 1995, and continue to set new records up to 0.278ƒÊm with a final goal of 0.23 ƒÊm. This result is attracting attention worldwide, leading to the development of free electron laser devices in the X-ray region.

4. Development of TeraHertz band super-high-speed optically-controlled optical modulating element
   With quantum well structure layered with two semiconductors with different band gaps, discrete electron energy levels (sub-bands) are generated in the well. We are developing a TeraHertz band super-high-speed optically-controlled optical modulating element by irradiating a beam of light with the wavelength corresponding to the difference in energy between two sub-bands to reduce electron density at low level with resonant excitation, and using the resultant increased interband absorption of electrons and positive holes.

5. Creation of new materials with selective excitation of molecular vibration using free electron laser
   Since local excitation of (selective excitation of certain structures in) amorphous material enables us to reduce disturbances in crystal structures and to modify the electrical characteristics of semiconductor such as electrical conductivity, we are attempting to crystallize SiC at a low temperature which can operate at high temperature and to make a-Si solar cells that have a longer lifetime.

6. Development of new process/altering technology using selective excitation of molecular vibration
   While the teeth and cholesterol are decomposed conventionally by lasers by vibrating the whole molecular structure, we are developing a new process and decomposition technology that utilizes the energy of a free electron laser by exciting or vibrating molecular structures locally or selectively while varying the wavelength of the free electron laser.

7. Si isotope separation using ??Bunshi Ho?? laser
   There are three types of Si isotope: 28Si (~92%), 29Si (~5%), and 30Si (~3%). Since 30Si changes to 31P in the (n,g) reaction, P can be uniformly doped into Si. Our experiment is the first attempt at vibrating/exciting Si compounds using a strong 10.5ƒÊm infrared-region free electron laser to separate isotopes of 30Si, targeting 30% enrichment.

Target groups:

Partners / Actors in the Project:

Mitsubishi Electric Corporation

Sumitomo Electric Industries, Ltd.

Kansai Electric Power Co. Inc.

Mitsubishi Heavy Industries, Ltd.

Hitachi, Ltd.

Toshiba Corporation

Matsushita Electric Industrial Co., Ltd.

Ishikawajimaharima Heavy Industries, Ltd.

Kobe Steel, Ltd.

NEC Corporation

Nissin Electric Co., Ltd.

Daihen Corporation

Institute for Laser Technology

Use of Information / Telematic Technologies:

JICST Document Information, Free Electron Laser Research Institute(FELI)HomePage, and others

Benefits to the Information Society:

1. Utilization of internucleus coupling bond resonance wavelength of FEL
   Most of the conventional types of laser (gas, liquid, solid, or semiconductor) use a fixed wavelength concentrated around NIR, Visible, and UV regions (1.5 - 0.2ƒÊm). Conventional FIR - IR (100 - 1.5ƒÊm) lasers include only a few types such as CO2 laser, CO laser, and Er-YAG laser.

   So therefore, as conventional lasers use only certain restricted portions of the spectrum for their operation, it follows from this that new applications may be found for lasers using these currently-unexploited wavelengths. Given the FEL laser's broad spectral coverage from the far-infrared through the ultra-violet region, including these currently-unexploited wavelengths, it is a natural candidate for the exploration and development of new applications using these portions of the spectrum.

   These applications may include: polishing and surface hardening of the teeth using a wavelength of 9.4ƒÊm taking advantage of the resonance of the PO4 coupling bond of hydroxyapatite which forms an enamel-like substance as mentioned above. Other applications include the evaluation of characteristics of TeraHertz band semiconductor super-grid structure as a super high-speed device; and creation of new materials using lattice vibration phenomena as the vibrating/exciting Si compounds using a 12.6ƒÊm free electron laser.

2. Practical uses suited to FEL's short-pulse high-power characteristics
   These characteristics, in addition to the variable wavelength mentioned earlier, should be very useful to reduce the (often detrimental) heat effects on objects irradiated by laser energy. In particular, FEL lasers with a wavelength of 6.4ƒÊm can be used as laser scalpels, or used to puncture the cell membrane of a lymphocyte without damaging the cell's cytoplasm. An FEL laser tuned to a wavelength of 9.4ƒÊm may be used, for example, for the removal of hemorrhoids or in the polishing and surface hardening of the teeth. These are only a few examples--we expect that more medical applications will be found in the future, which will take advantage of the unique properties of the FEL laser. It is entirely conceivable that a new medical equipment industry may be based on the FEL laser's medical uses.

3. Ultra sonic effects of FEL
   Although the ultra sonic effects are still largely unknown, internucleus bond resonance effects and internucleus interactions induced by the effects of supersonic shock waves should be further studied. This may well be a tool which can be used to cultivate a new scientific frontier.

Expected Cost:

8.6311 billion yen

Annual Budget(Unit: billion yen)

Fiscal Year	Budget
FY1990	0.2134
FY 1991	0.2828
FY 1992	1.1006
FY 1993	2.0260
FY 1994	2.5830
FY 1995	1.7354
FY 1996	0.6890

Date Information was Collected:

November 15, 1995

Date of Last Update:

December 22, 1997
October 23, 1998

Infomation provided by:

Free Electron Laser Research Institute, Inc.

• Name:
• Position:
• Mailing address: 2-9-5 TsudaYamate, Hirakata, Osaka, 573-01 Japan
• Phone: +81-720-96-0414
  
• FAX: +81-720-96-0421
  
• E-mail:

Other infomation:

For the latest news on the project please go to
http://www.feli.co.jp/English/index.html

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