Terahertz range diode based on electron field emission of AlGaN microcathode

Small-signal negative conductance of a diode on AlGaN micro-cathode resulted from delay of electron both emission and transit in vacuum layer has been investigated. Its periodic dependence on both of delay angles leads to multiband structure of diode negative conductance spectrum when upper angle of emission delay in the spectrum exceeds the same of transit delay. Owing to sufficiently great values of electric field and electron velocity in vacuum the spectrum is in terahertz frequency range. Dependences of spectrum parameters, negative conductance maximum and its frequency on both of the delays have been found.