Design of TE_6,2 Denisov launcher in 3 mm gyrotron

A Denisov launcher for transforming TE6,2 mode to Gaussian-like mode is proposed to be employed in 3 mm Gyrotron. Based on the mode coupling theory, the design method of the Denisov launcher is shown. By adopting developed mathematical programme, the TE6,2 Denisov launcher is studied using the concrete parameters of the 3 mm whispering gallery mode gyrotron, with its length of 52 mm. It is verified by electromagnetic field simulation that, the launchers wall current of the cut edges decreases to 10% of the central focused current. The cold test result of Denisov mode converter is better than that of Vlasov mode converter.