Splitting of the resonance levels of double-barrier structures in a high microwave electric field

The dependence of the width and shape of the resonance levels of asymmetric double-barrier resonance-tunneling structures with high narrow barriers on the amplitude of the resonance microwave field and specific features of the electron transport in the case of ballistic passage of electrons near the resonance levels has been investigated. It has been found that a resonance level can be first broadened significantly and be further split into two absolutely transparent levels with an increase in the microwave field amplitude. The conditions have been formulated under which nonresonance scattering channels near the resonance levels also become absolutely transparent.