PIC simulation study of electron gun with rotational surface cathode

Abstract

The electron gun with rotational surface cathode is presented to improve the laminarity of the converging electron beams in this paper, and the function expression of the rotational surfaces is given. The results of particle in cell (PIC) simulation indicate that anode-hole spherical aberration is the major cause for the nonlaminarity of the electron beams. By properly choosing the size of the shape, rotational surface cathode can effectively counteract the effect of the anode-hole spherical aberration and enhance the laminarity of the electron beams. The theoretical analysis was carried out for the explanation of the phenomenon that appeared in the PIC simulation.

Keywords

rotational surface cathode / laminarity / anode-hole spherical aberration

References

[1] Pierce J R. Rectilinear electron flow in beams. Journal of Applied Physics, 1940, 11(8): 548–554

[2] Ashkin A. Dynamics of electron beams from magnetically shield guns. Journal of Applied Physics, 1958, 29(11): 1594–1604

[3] Brewer G R. Some characteristics of a magnetically focused electron beam. Journal of Applied Physics, 1959, 30(7): 1022–1038

[4] Harker K J. Nonlaminar flow in cylindrical electron beams. Journal of Applied Physics, 1957, 28(6): 645–650

[5] Nagy G A, Szilagyi M. Introduction to the Theory of Space Charge Optics. London: Macmillan Press Ltd, 1974, 118–122

[6] Brian M. Design of an electron gun using computer optimization. IEEE Transactions on Plasma Science, 2004, 32(3): 1242–1250

[7] Shimada T, Nishimaki M. A method of reducing the effects of anode aperture in high-perverance convergent electron guns. IEEE Transactions on Electron Devices, 1968, 15(11): 907–914

[8] Editorial Committee of Electronic Tube Design Handbook. Design Manual of Electron Optics System of Microwave Tube. Beijing: National Defense Industry Press, 1981, 36–39 (in Chinese)

[9] Lewis B N, Tran H T, Ives R L, Read M. Design of an electron gun using computer optimization. IEEE Transactions on Plasma Science, 2004, 32(3): 1242–1250

[10] David J A, Ives R L, Tran H T, Bui T, Read M E.Computer optimized design of electron guns. IEEE Transactions on Plasma Science, 2008, 36(1): 156–168

[11] Nusinovich G S,Levush B, Abe D K. A review of the development of multiple beam klystrons and TWTs. Washington D C: Naval Research Laboratory, MemoNRL/MR/6840-03-8673, 2003

[12] Ives R L, Attarian A, Bui T, Read M, David J, Tran H, Tallis W J, Davis S, Gadson S E, Blach N, Brown D, Kiley E. Computational design of asymmetric electron beam devices. IEEE Transactions on Electron Devices, 2009, 56(5): 753–761

[13] Herrmannafeldt W B. EGUN — An Electron Optics and Gun Design Program. Stanford: Stanford Linear Accelerator Center, 1988

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg