“…In the material of the third layer -M III, the aluminum content is higher than in the materials of the second and fourth layers, but less than in the materials of the first and fifth layers of the structure. Thus, in the second, third, and fourth layers above the potential barrier of the third layer and between the potential barriers of the first and fifth layers, a quasicontinuum zone is formed, since the carriers in the second and fourth layers experience quantum confinement, their thickness does not exceed the de Broglie wavelength, the thickness of the separation barrier is also small since the barrier is considered to be permeable; however, the total distance between the barriers of the first and fifth layers, in the general case, can approach the values of a bulk sample [5][6][7].…”