Fig. 1. (Color online) (a) Layer structure and (b) XRD curves of (Al,Ga)Sb/InAs 2DEGs. The blue line in (b) indicates the calculated diffraction angle of unstrained InAs (004) plane.

Fig. 2. (Color online) AFM images (5 × 5 μm²) of (a) sample A, (b) sample B1, (c) sample B2, (d) sample B3, and (e) sample B4. The left-hand and right-hand images in (a)–(e) correspond to the 2D and 3D surface morphology, respectively.

Fig. 3. (Color online) (a) Schematic diagram of Hall bar devices with the current along the [–110] and [110] directions. (b) Sheet resistances as a function of temperature, (c) Hall resistances as a function of magnetic field, and (d) electron sheet concentrations as a function of temperature along the [–110] and [110] directions for sample A.

Fig. 4. (Color online) (a) Temperature dependence of electron mobilities along the [–110] and [110] directions for sample A. (b)μ_[–110]/μ_[110] and N_S[–110]/N_S[110] as a function of temperature for sample A.

Fig. 5. (Color online) (a) Temperature dependence of μ_[–110]/μ_[110] and N_S[–110]/N_S[110] for sample B1. (b) μ_[–110]/μ_[110] as a function of temperature for samples B1–B4.

Table 1. Detailed information of A and series-B samples.