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Register a new userThe effect of the electron-beam parameter spread on microwave generation in a three-cavity axial vircator
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Added by
Alexandra Gurinovich
Publication date
2014
fields
Physics
and research's language is
English
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The behavior of the generation efficiency and radiation spectrum of a three-cavity axial vircator versus the radius of the injected electron beam, its impedance and energy homogeneity is studied. This paper establishes that for each geometry of a three-cavity resonator, there exist the optimal (maximizing the generation efficiency) values of these parameters and determines the range within which they may vary without losing the efficiency of generation.
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We demonstrate the strong coupling between an electron spin ensemble and a three-dimensional cavity in a reflection geometry. We also find that an anticrossing in the cavity/spin spectrum can be observed under conditions that the collective coupling strength $g_c$ is smaller than the spin linewidth $gamma_s$ or the cavity linewidth. We identify a ratio of $g_c$ to $gamma_s$ ($g_c/gamma_s >$ 0.64) as a condition to observe a splitting in the cavity frequency. Finally, we confirm that $g_c$ scales with $sqrt{N}$, where $N$ is the number of polarized spins.
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