NOISE IN RESISTIVE-WALL AMPLIFIER OF M-TYPE WITH "THICK" BEAM

The aim of our research is to study the noise in the resistive-wall amplifier with crossed electric and magnetic fields with a beam of finite thickness. The theory of the O-type resistive-wall amplifier is well known, at least as a classical example of using of waves with negative energy. Theory of resistive-wall amplifier M-type, in which negative energy waves are also used, has not been studied until recently. It seems interesting to study noise in a device with crossed fields, especially since early work mentioned a possible low noise level. Method. Study of noise based of the previously constructed two-dimensional linear adiabatic theory of a device with an electron flux of finite thickness that moves in crossed static electric and magnetic fields (magnetron-type flux) between two flat surfaces with complex conductivity. The noise coefficient in such a device is first studied. The cases when both surfaces are metallic, or when one of the surfaces is metallic, and the other has active, capacitive or inductive conductivity are considered. Results and discussion. It is shown that the complex conductivity of one of the surfaces, when the other is metallic, does not give a noticeable advantage either in increasing the gain factor or in reducing the noise factor in comparison with the case of both metal surfaces. It is shown that obtaining larger gain and lowest noise figure correspond to the fill factor of the order of one.