Large effective mass enhancement of the InAs1−xNx alloys in the dilute limit probed by Shubnikov-de Haas oscillations

Transport properties of two-dimensional electron gases formed in low-nitrogen-content InAs1−xNx/InGaAs single quantum wells have been investigated using Shubnikov-de Haas (SdH) oscillations. We determine the nitrogen-content-dependent two-dimensional carrier concentration and electron effective mass by analyzing the SdH oscillation function. The carrier mobility decreases with the increase of nitrogen composition, suggesting some deterioration of crystal quality. Our result shows that even in the dilute alloy limit, the electron effective mass increases considerably, and such an enhancement cannot be explained by the present simple band anticrossing model.