Frequency Tunable sub-THz Gyrotrons for Spectroscopy ApplicationsA. E. Fedotov, I. V. Zotova, M. Yu. Glyavin, R. M. Rozental, A. S. Zuev, N. S. Ginzburg, A. S. Sergeev and T. IdeharaEPJ Web Conf., 187 (2018) 01025DOI: https://doi.org/10.1051/epjconf/201818701025