Selective soft mode heating in a ferroelectric film

Paraelectric in a strong high-frequency field

“…Another method of eliminating this difficulty consists in using a high-frequency alternating electric field, rather than dc voltage (video pulses) as control signals. If the frequency of this field is close to that of a natural soft mode (10 11 −10 12 Hz) and the amplitude is sufficiently large, the phonon subsystem of the material will pass to a nonequilibrium state corresponding to soft-mode "overheating" and, hence, the permittivity ε will exhibit a rapid change [5].…”

“…Another method of eliminating this difficulty consists in using a high-frequency alternating electric field, rather than dc voltage (video pulses) as control signals. If the frequency of this field is close to that of a natural soft mode (10 11 −10 12 Hz) and the amplitude is sufficiently large, the phonon subsystem of the material will pass to a nonequilibrium state corresponding to soft-mode "overheating" and, hence, the permittivity ε will exhibit a rapid change [5].The present investigation was aimed at establishing frequencies of such an external signal, which would provide the most effective control over a nonlinear element at a minimum heating of the material by the highfrequency field. It should be noted that the direct (quasi-equilibrium) heating of the element by an external field also leads to a change in the permittivity and can be considered as a means of controlling the capacitance.…”