Nonmonotonous Electron Mobility in Double Quantum Well Pseudomorphic High Electron Mobility Transistor Structure

Non-monotonic mobility
$\mu$
of electrons is obtained in a pseudomorphic GaAs/In
x
Ga
1-x
As high electron mobility transistor having a double quantum well structure with asymmetric doping concentrations in the outer barriers. A dip in
${\mu}$
occurs at the resonance of subband states because of the shift of the subband wave functions, which affects the subband mobilities limited by interface roughness scattering. The dip in
$\mu$
amplifies with increase in the asymmetry of the width of wells.