Research

Energy Generation and Utilization by Controling High Power Electromagnetic Waves and Charged Particle Beam

Establishment of the technologies to control the interaction between electromagnetic waves and charged particles brings great benefit for human race in the 21st century. In our laboratory, we are working on various themes related to electromagnetic waves and charged particles. One topic is about fusion plasma, which is generated and heated up by the high power microwave. We are working on understanding and improving the confinement of fusion plasma and developing the system for heating and current drive. Another topic is about ultra-small discharge-type fusion device for neutron or proton source, which is expected to be applied for various purposes such as mine detection, explosive or illegal chemical detection ex. at airports, medical use. The other topic is about high brightness electron beam generation and energy conversion of charged particle beam by electromagnetic field for advanced quantum radiation source, which is represented by free electron laser.





Analysis of Plasma Production and Measurement of High Temperature Plasma

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Plasma Measurement with Microwave

It is well known that dolphins or bats use supersonic wave to get structural information from their surroundings. For plasma, same method by microwave can be applied to know the plasma density and its fluctuation at the reflection point. Incident microwave is reflected at the cut-off layer dependent on the microwave frequency. With this method, non-contact measurement of high temperature (millions of celsius degree) plasma can be done.
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Measuring Plasma Turbulence

It is widely confirmed in natural world that turbulence forms structure. The well-known example of this kind of structure is "Stripe" structure of Jupiter. This is named "zonal flow" that is formed automatically by the turbulence itself. Such structure is also be formed in plasma. Plasma confinement gets better or worse depending on this structure. Measurement of the plasma turbulence and its structure accelerates the understanding about plasma confinement and it also leads a better understanding about the natural phenomena.
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Plasma Heating

There are several ways to heat plasmas.
  1. Ohmic heating by plasma current.
  2. Heating by electron cyclotron waves just like as microwave oven.
  3. Neutral Beam Injection (NBI): Heating by injecting high energy neutral beam into plasmas.