Effect of low nitrogen concentrations on the electronic properties of InAs1-xNx

We report cyclotron resonance (CR), transverse magnetoresistance (MR), and Hall effect studies of a series of n-type InAs1-xNx epilayers grown on GaAs with x up to 1%. The well-resolved CR absorption lines, the classical linear MR, Shubnikov-de Haas magneto-oscillations, and negative MR revealed in our experiments provide a means of probing the effect of the N atoms on the electronic properties of this alloy system and reveal qualitative differences compared to the case of the wider gap III-N-V compounds, such as GaAs1-xNx. In GaAs1-xNx electron localization by N levels that are resonant with the extended band states of the host crystal act to degrade the electrical conductivity at small x (similar to 0.1%). These phenomena are significantly weaker in InAs1-xNx due to the smaller energy gap and higher energy of the N levels relative to the conduction band minimum. In InAs1-xNx the electrical conductivity retains the characteristic features of transport through extended states, with electron coherence lengths (l(phi) similar to 100 nm at 2 K) and electron mobilities (mu = 6 x 10(3) cm(2) V-1 s(-1) at 300 K) that remain relatively large even at x=1%.