Ultra-High Velocity Ratio in Magnetron Injection Guns for Low-Voltage Compact Gyrotrons
Abstract
:1. Introduction
2. Theoretical Calculation
2.1. Sensitivity Analysis of α for Axisymmetric Electric and Magnetic Field
2.2. Space Charge Limits
2.3. Velocity Spread
2.4. Summary
3. Numerical Simulation by Magic 2D PIC Code
4. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
- Thumm, M. State-of-the-art of high-power gyro-devices and free electron masers. J. Infrared Millim. Terahertz Waves 2020, 41, 1–140. [Google Scholar]
- Kartikeyan, M.V. Gyrotrons-high-power microwave and millimeter wave technology. In Advanced Texts in Physics; Springer Scientific: Berlin, Germany, 2004. [Google Scholar]
- Bratman, V.L.; Fedotov, A.E.; Kalynov, Y.K.; Makhalov, P.B.; Osharin, I.V. Numerical Study of a Low-Voltage Gyrotron (“Gyrotrino”) for DNP/NMR Spectroscopy. IEEE Trans. Plasma Sci. 2017, 45, 644–648. [Google Scholar] [CrossRef]
- Glyavin, M.Y.; Zavolskiy, N.A.; Sedov, A.S.; Nusinovich, G.S. Low-voltage gyrotrons. Phys. Plasm. 2013, 20, 033103. [Google Scholar] [CrossRef]
- Manuilov, V.N.; Morozkin, M.V.; Luksha, O.I.; Glyavin, M.Y. Gyrotron collector systems: Types and capabilities. Infrared Phys. Technol. 2018, 91, 46–54. [Google Scholar] [CrossRef]
- Kishko, S.A.; Ponomarenko, S.S.; Kuleshov, A.N.; Zavertanniy, V.V.; Yefimov, B.P.; Alexeff, I. Low-voltage cyclotron resonance maser. IEEE Trans. Plasma Sci. 2013, 41, 2475–2479. [Google Scholar] [CrossRef]
- Kuleshov, A.; Ishikawa, Y.; Tatematsu, Y.; Mitsudo, S.; Idehara, T.; Khutoryan, E.; Kishko, S.; Ponomarenko, S.; Glyavin, M.; Bandurkin, I.; et al. Low-voltage operation of the double-beam gyrotron at 400 GHz. IEEE Trans. Electron Devices 2020, 67, 673–676. [Google Scholar] [CrossRef]
- Manuilov, V.N.; Tsvetkov, A.I.; Glyavin, M.Y.; Mitsudo, S.; Idehara, T.; Zotova, I.V. Universal electron gun design for a CW third harmonic gyrotron with an operating frequency over 1 THz. J. Infrared Millim. Terahertz Waves 2020, 41, 8–9. [Google Scholar] [CrossRef]
- Nusinnovich, G.S. Introduction to the Physics of Gyrotrons; Johns Hopkins Univercity Press: Barltimore, MD, USA, 2012. [Google Scholar]
- Kreischer, K.E.; Kimura, T.; Danly, B.G.; Temkin, R.J. High-power operation of a 170 GHz megawatt gyrotron. Phys. Plasmas 1997, 4, 1907–1914. [Google Scholar] [CrossRef]
- Hornstein, M.K.; Bajaj, V.S.; Griffin, R.G.; Temkin, R.J. Efficient low-voltage operation of a CW gyrotron oscillator at 233 GHz. IEEE Trans. Plasma Sci. 2007, 35, 27–30. [Google Scholar] [CrossRef]
- Joye, C.D.; Griffin, R.G.; Hornstein, M.K.; Hu, K.N.; Kreischer, K.E.; Rosay, M.; Shapiro, M.A.; Sirigiri, J.R.; Temkin, R.J.; Woskov, P.P. Operational characteristics of a 14-W 140-GHz gyrotron for dynamic nuclear polarization. IEEE Trans. Plasma Sci. 2006, 34, 518. [Google Scholar] [CrossRef] [Green Version]
- Torrezan, A.C.; Han, S.; Mastovsky, I.; Shapiro, M.A.; Sirigiri, J.R.; Temkin, R.J.; Barnes, A.B.; Griffin, R.G. Continuous-Wave Operation of a Frequency-Tunable 460-GHz Second-Harmonic Gyrotron for Enhanced Nuclear Magnetic Resonance. IEEE Trans. Plasma Sci. 2010, 38, 1150–1159. [Google Scholar] [CrossRef] [PubMed]
- Torrezan, A.C.; Shapiro, M.A.; Sirigiri, J.R.; Temkin, R.J.; Griffin, R.G. Operation of a continuously frequency-tunable second-harmonic CW 330-GHz gyrotron for dynamic nuclear polarization. IEEE Trans. Electron Devices 2011, 58, 2777–2783. [Google Scholar] [CrossRef] [Green Version]
- Jawla, S.K.; Griffin, R.G.; Mastovsky, I.A.; Shapiro, M.A.; Temkin, R.J. Second harmonic 527-GHz gyrotron for DNP-NMR: Design and experimental results. IEEE Trans. Electron Devices 2019, 99, 1–7. [Google Scholar] [CrossRef] [PubMed]
- Ausu, L.; Idehara, T.; Ogawa, I. Design of a compact CW THz gyrotron. In Proceedings of the 34th International Conference Infrared, Millimeter, Terahertz Waves, Busan, Korea, 21–25 September 2009; pp. 1–2. [Google Scholar]
- Kumar, N.; Singh, U.; Khatun, H.; Kumar, A.; Singh, T.P.; Sinha, A.K. Sensitivity Analysis of Electron Beam Velocity Ratio for 42 GHz, 200 kW Gyrotron; Frequenz: Berlin, Germany, 2010; Volume 64, pp. 93–96. [Google Scholar]
- Edgcombe. Gyrotron Oscillators: Their Principles and Practice; Taylor and Francis: London, UK, 1993. [Google Scholar]
- Drobot, A.T.; Kim, K. Space charge effects on the equilibrium of guided electron flow with gyromotion. Int. J. Electron. 1981, 51, 351–367. [Google Scholar] [CrossRef]
- Gilmour, A.S.; Ebrary, I. Klystrons, Traveling Wave Tubes, Magnetrons, Cross-Field Amplifiers, and Gyrotrons; Artech House: Norwood, MA, USA, 2011. [Google Scholar]
- Ganguly, A.K.; Chu, K.R. Limiting current in gyrotrons. Int. J. Infrared Millim. Waves 1984, 5, 103–121. [Google Scholar] [CrossRef]
- Singh, A.; Jain, P.K. Effects of electron beam parameters and velocity spread on radio frequency output of a photonic band gap cavity gyrotron oscillator. Phys. Plasmas 2015, 22, 3945. [Google Scholar] [CrossRef]
- Fokin, A.P.; Glyavin, M.Y.; Nusinovich, G.S. Effect of ion compensation of the beam space charge on gyrotron operation. Phys. Plasmas 2015, 22, 351. [Google Scholar] [CrossRef]
- Tsimring, S.E. Gyrotron electron beams: Velocity and energy spread and beam instabilities. Int. J. Infrared Millim. Waves 2001, 22, 1433–1468. [Google Scholar] [CrossRef]
- Kuftin, A.N.; Lygin, V.K.; Tsimring, S.E.; Zapevalov, V.E. Numerical simulation and experimental study of magnetron-injection guns for powerful short-wave gyrotrons. Int. J. Electron. 1992, 5, 1145–1151. [Google Scholar] [CrossRef]
- Nguyen, K.T.; Danly, B.G.; Levush, B.; Blank, M.; True, R.; Good, G.R.; Hargreaves, T.A.; Felch, K.; Borchard, P. Electron gun and collector design for 94-GHz gyro-amplifiers. IEEE Trans. Plasma Sci. 1998, 26, 799–813. [Google Scholar] [CrossRef]
- Fu, W.; Yan, Y.; Liu, S. Study on a 60 kV/5 A magnetron injection gun for 200 GHz electron cyclotron master. Front. Electr. Electron. Eng. China 2009, 4, 440. [Google Scholar] [CrossRef]
Institution | Voltage | Current | Pitch Factor(α) | Velocity Spread | Power | Efficiency |
---|---|---|---|---|---|---|
MIT [11,12,13,14,15] | 3.5 kV | 50 mA | 2 | 8% | 12 W | 6.8% |
12.3 kV | 25 mA | No Mention | 14 W | 4% | ||
13 kV | 100 mA | 2 | 4% | 16 W | 1.2% | |
10.1 kV | 190 mA | 2 | 4% | 18 W | 0.9% | |
16.65 kV | 110 mA | 1.8 | 3% | 9.3 W | 0.5% | |
FIR FU [16] | 10 kV | 50 mA | No Mention | 10 W | 2% | |
MIT (Massachusetts Institute of Technology) FIR FU (Research Center for Development of Far-Infrared Region, University of Fukui) |
Parameters | Value |
---|---|
Operating Mode | TE01 |
Beam Voltage (Ub) | 10 kV |
Beam Current (Ib) | 0.5 A |
Output Power (P) | 0.5 kW |
Output Frequency (f) | 75 GHz |
Main Magnet (B0) | 2.7 T |
Parameters | Value |
---|---|
The guiding radius (Rg) | 1.2 mm |
The inner radius (Ri) | 1.1 mm |
The outer radius (Ro) | 1.3 mm |
The interaction radius (Ra) | 2.45 mm |
Parameters | Value |
---|---|
Max Velocity (αmax) | 2.5 |
Velocity Spread (δβ⊥rms) | 10% |
Voltage Depression (Vdep) | 286 V |
Parameters | Value |
---|---|
Modulating Voltage (Umod) | 7.5 kV |
Average Radius of Cathode (Rc) | 4.65 mm |
Thickness of Emitter Ring (Ls) | 1.5 mm |
Tilt Angle of Cathode (θc) | 18.4° |
Distance between Cathode and Modulating Anode (d) | 3.91 mm |
Parameters | Value |
---|---|
Average Beam Radius (Rg) | 1.2 mm |
Velocity Ratio (α) | 2.55 |
Perpendicular Velocity Spread Ratio () | 9.33% |
Full Radial Width | 0.22 mm |
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Lu, D.; Fu, W.; Guan, X.; Yang, T.; Zhang, C.; Chen, C.; Han, M.; Yan, Y. Ultra-High Velocity Ratio in Magnetron Injection Guns for Low-Voltage Compact Gyrotrons. Electronics 2020, 9, 1587. https://doi.org/10.3390/electronics9101587
Lu D, Fu W, Guan X, Yang T, Zhang C, Chen C, Han M, Yan Y. Ultra-High Velocity Ratio in Magnetron Injection Guns for Low-Voltage Compact Gyrotrons. Electronics. 2020; 9(10):1587. https://doi.org/10.3390/electronics9101587
Chicago/Turabian StyleLu, Dun, Wenjie Fu, Xiaotong Guan, Tongbin Yang, Chaoyang Zhang, Chi Chen, Meng Han, and Yang Yan. 2020. "Ultra-High Velocity Ratio in Magnetron Injection Guns for Low-Voltage Compact Gyrotrons" Electronics 9, no. 10: 1587. https://doi.org/10.3390/electronics9101587
APA StyleLu, D., Fu, W., Guan, X., Yang, T., Zhang, C., Chen, C., Han, M., & Yan, Y. (2020). Ultra-High Velocity Ratio in Magnetron Injection Guns for Low-Voltage Compact Gyrotrons. Electronics, 9(10), 1587. https://doi.org/10.3390/electronics9101587