Magnetotransport properties of two‐dimensional channels in pseudomorphic and strain relaxed In_0.17Ga_0.83As heterojunctions Available to Purchase

The electrical and galvanomagnetic properties of the two‐dimensional electron gas present in pseudomorphic In_0.17Ga_0.83As/Al_0.35Ga_0.65As and in strain‐relaxed In_0.17Ga_0.83As/In_0.15Al_0.85As modulation δ‐doped heterojunctions were measured as a function of temperature using conventional Hall and resistivity measurements and 1.6 K Shubnikov de Haas oscillatory magnetoresitance measurements, which revealed single subband occupancy. Typical mobilities of the pseudomorphic specimens are, μ_{(300 K)}=9.3×10³ cm²/V s and μ_{(1.6 K)}=5.51×10⁴ cm²/V s for electron densities, n_s=1.07×10¹² cm⁻² and 9.78×10¹¹ cm⁻², respectively. The strain‐relaxed structures have higher electron mobilities, μ_{(300 K)}=10⁴ cm²/V s and μ_{(1.6 K)}=7.61×10⁴ cm²/V s for n_s=9.37×10¹¹ cm⁻² and 8.67×10¹¹ cm⁻². Although the total scattering time τ_q calculated from the magnetic field‐dependent amplitudes of their Shubnikov de Haas oscillations, is half that of the pseudomorphic structures, their low temperature, classical relaxation time τ_c is greater by 30%.