繞軸式電子槍所產生繞軸式的電子束被發展來驅動太赫茲諧波的磁旋裝置，諧波的交互作用能夠降低對磁場的要求，但會產生較嚴重的模式競爭。而繞軸式電子束能夠抑制在交互作用區段所產生的競爭模態。
對於電子動力學所研究的繞軸式電子槍發現在靠近發射帶所設計的電極，能夠產生集中且加速的電場，去平衡掉空間電荷效應的影響，以及磁旋半徑的偏差。在極力的優化之後，能夠用0.53 A的電流在作用區磁場大小3.35 T的強況下，產生一個速度比1.32、軸向速度發散9.98%的低電壓的繞軸式電子槍，這些優勢使得諸如TM11模式的反波振盪器的低電壓磁旋裝置得以開始發展。
在不特別需要特別大功率(>100000 W)的前提下，低電壓所提供的功率已足夠提供給一般使用，且有利於能夠大幅縮減設備價錢及尺寸，以及降低能源成本，將來也可朝桌上型裝置發展。

Axis-encircling gun is being developed to generate an axis-encircling beam to drive the terahertz harmonic gyro-devices. The harmonic interaction is able to mitigate the requirement of the magnetic field but suffer from serious mode competitions. The axis-encircling beam, however, is capable of suppressing the competing modes inside the interaction region. The study of the electron dynamics in the axis-encircling gun reveals that electrodes close to the emitter are employed to construct a focusing-accelerating electric field to balance the space-charge influence and guiding center deviation. Intensive optimization generates a low-voltage axis-encircling gun with a pitch factor of 1.32 and minimum axial velocity spread of 9.98% at a magnetic field of 3.35 T and a beam current of 0.53 A. These merits enable the low-voltage gyro-devices, like the TM11 mode gyrotron backward-wave oscillator to be developed. If the work above can be realized, lowering the voltage while maintaining a good efficiency of electron beam can result in a reduction of the cost of energy and the size of the equipment, that make portable gyrotron possible.

摘要
目錄
第一章 緒論-----------------------------10
1.1 太赫茲簡介--------------------------10
1.2 磁旋管種類--------------------------12
1.3 磁旋管的電子迴旋脈射(ECM)原理--------14
1.4 電子槍簡介--------------------------16
第二章 電子槍理論之探討------------------21
2.1 繞軸式電子槍特性--------------------21
2.2 電子運動方程式----------------------24
2.3 電子槍的設計理論--------------------25
2.4 重要參數的討論----------------------27
2.5 電子槍的理論限制探討-----------------31
2.6 電子槍的設計方法---------------------39
2.7 電子槍之磁鐵參數設計-----------------45
第三章 模擬結果與分析--------------------46
3.1 模擬結果參數檢驗---------------------46
3.2 操作容忍度範圍測試-------------------47
第四章 結論-----------------------------51
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