Development of an improved carcinotron in the far infrared range

The improvement of a Carcinotron (Backward Wave Oscillator) working around a wavelength of 0.85 mm 20 percent tunability range is discussed. A gun was designed in order to increase the tuning bandwidth and the tube was tested with a lighter Samarium-Cobalt magnet. The tuning range achieved was increased by a factor of 1.35 as compared to the previous tube measurements inside a conventional Ticonal magnet and is comparable to the range measured when operating a previous model with an electromagnet. The mass of the magnet was reduced by a factor of three by use of the Samarium-Cobalt magnet.