0000000000114169

AUTHOR

Toshitaka Idehara

showing 6 related works from this author

High Cyclotron Harmonics Excitation in Multi-beam Terahertz Range Gyrotrons

2019

The paper presents recent results on the multi-beam gyrotrons operating at cyclotron harmonics in terahertz frequency range. The theoretical and experimental investigation of second harmonic 0.78 THz gyrotron includes comparison of generating and absorbing beam schemes, research on the effect of velocity spread and mode competition process, along with development of third harmonic 1.2 THz tube based on verified numerical codes and latest experimental results.

PhysicsRange (particle radiation)Terahertz radiationbusiness.industryCyclotronPhysics::Opticslaw.inventionOpticsPhysics::Plasma PhysicslawGyrotronHarmonicsHarmonicbusinessExcitationBeam (structure)2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring)
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Using of reflections for expansion of frequency tuning in a THz-band gyrotron

2017

Effect of delayed reflection on operation of a second-harmonic THz-band gyrotron is studied. Theoretical analysis, numerical calculations and experimental observations for the 0.394 THz FU CW IIB gyrotron are presented.

010302 applied physicsPhysicsbusiness.industryTerahertz radiation020206 networking & telecommunications02 engineering and technology01 natural sciencesMagnetic fieldlaw.inventionFrequency conversionOpticslawGyrotron0103 physical sciences0202 electrical engineering electronic engineering information engineeringReflection (physics)businessNumerical stability2017 Eighteenth International Vacuum Electronics Conference (IVEC)
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Experimental verification of a self-consistent calculation for continuous frequency-tune with a 400 GHz band second harmonic gyro-BWO

2013

A self-consistent code is introduced to develop a continuous frequency tunable gyro-BWO. A cavity is designed with TE8,5 mode for 400 GHz band second harmonic oscillation. The experimental verification has been carried out and 2 GHz tunability is observed with output powers of higher than 40 W.

PhysicsOpticsUhf oscillatorsbusiness.industryTerahertz radiationAcousticsHarmonicMode (statistics)Physics::OpticsSelf consistentbusinessHarmonic oscillator2013 38th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)
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Hysteresis and frequency tunability of gyrotrons

2015

We present the first devoted experimental and theoretical study of hysteresis phenomenon in relation to frequency tunability of gyrotrons.

HysteresisNuclear magnetic resonanceMaterials scienceCondensed matter physicsPhysics::Plasma PhysicslawTerahertz radiationGyrotronHysteresis phenomenonlaw.invention2015 40th International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz)
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Study of Mode Competition in the Third Harmonic Gyrotron with Inclusion of the Electron Velocity Spread and the Beam Width

2018

Influence of the electron velocity spread and the beam width on the mode competition and efficiency is investigated in the 1.185- THz third harmonic gyrotron to be used in dynamical nuclear polarization - nuclear magnetic resonance (DNP-NMR) spectrometer.

PhysicsBeam diameterSpectrometerTerahertz radiationbusiness.industryMode (statistics)Polarization (waves)01 natural sciences010305 fluids & plasmaslaw.inventionHarmonic analysisElectricity generationOpticslawGyrotron0103 physical sciencesNuclear Experiment010306 general physicsbusiness2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)
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Calculations of Starting Currents and Frequencies in Frequency-Tunable Gyrotrons

2012

Cold cavity and self-consistent formalisms for starting current and frequency calculations in frequency-tunable gyrotrons are summarized. Numerical solution schemes of the corresponding equations are discussed. A specific case is analyzed in detail.

ChemistryGeneral EngineeringGeneral Physics and AstronomyThermodynamicsCurrent (fluid)Rotation formalisms in three dimensionsComputational physicsJapanese Journal of Applied Physics
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