Ballistic transport in triple-barrier structures in two frequency electric field

For asymmetric triple-barrier resonant-tunneling structures with thin and high (delta) barriers, the closed form of solution of Schrödinger equation describing the resonant transitions between three quantum levels in the single-frequency high electric field has been generalized for the case of double-frequency field. It is shown that for each structure there are conditions when the majority of electrons falling on the upper energy level might emit two photons and then leave the structure without intermediate electron-phonon interaction.