Parity and resonance levels expansion in triple-barrier quantum structures under HF electric field

Exact analytical steady-state solution of the time-dependence Schrodinger equations at resonance in small signal HF electric field is found as well as expression for HF active conductivity. Very simple method for calculation of quantum levels width has been generalized and expression for quantum levels width of triple-barrier structures has been obtained. This method is based on analysis of determinant of liner equation set for electron transport in quantum structure. It is shown that if the levels in each quantum well forming the resonance level of the whole structure have the different parity, the resonance level width and integral HF structure conductance can rise many times. Respectively, the electron life time in structure decreases many times, so the conditions for electron to leave the structure without electron-phonon collision can be simply realized, so one has the real way for ballistic electron transport quantum-cascade laser realization