Field effect transistor with a quantum-wave interference layer

A field effect transistor comprising:

• a quantum-wave interference layer having plural periods of a pair of a first layer and a second layer, said second layer having a wider band gap than said first layer, and said quantum-wave interference layer being formed in a region adjacent to a channel;
• wherein each thickness of said first and said second layers is equal to an odd number multiplied by one fourth of a quantum-wave wavelength of carriers in each of said first and said second layers, which exist around the lowest energy level of said second layer,
• wherein said wavelength λW in said first layer is equal to λW=h/[2mW(E+V)]½, said wavelength λB in said second layer is equal to λB=h(2mBE)½, said thickness of said first layer DW is equal to DW=nWλW/4, and said thickness of said second layer DB is equal to DB nBλB/4, wherein h, mW, mB, E, V, and nW and nB represent Plank's constant, an effective mass of said carrier in said first layer, an effective mass of said carrier in said second layer, a kinetic energy of carriers at the lowest energy level around said second layer, a potential energy of said second layer to said first layer, and odd numbers, respectively, and wherein E≦V/9.