Bloch oscillations in superlattices: The problem of a terahertz oscillator

The feasibility of designing a terahertz oscillator based on the Bloch oscillations of electrons in semiconductor superlattices is studied. It is shown that superlattices with high-Q Bloch oscillations can be used to generate a terahertz emission in pulsed electric fields with an off-duty factor that ensures the thermalization of electrons heated by the field. It is suggested that a terahertz oscillator is designed with a frequency that is tuned continuously by an electric field on the basis of anharmonic Bloch oscillations of electrons in semiconductor superlattices that have special miniband characteristics in which the major part of the effective electron mass is positive and increases as the electron energy increases. This circumstance makes it possible to eliminate the development of undesired domain instability (the Gunn effect). (C) 2005 Pleiades Publishing, Inc.