Transport properties and observation of quantum Hall effects of InAs 0.1 Sb 0.9 thin layers sandwiched between Al 0.1 In 0.9 Sb layers

InAs0.1Sb0.9 active layers sandwiched between Al0.1In0.9Sb insulating buffer layers were grown on GaAs (100) substrates by molecular beam epitaxy. The basic transport properties at room temperature and quantum Hall effects at low temperature of the InAs0.1Sb0.9 were studied as a function of InAs0.1Sb0.9 thickness. The electron mobility of the InAs0.1Sb0.9 active layers had a very high value and very small thickness dependence at less than 500nm. The quantum Hall effects of the InAs0.1Sb0.9 were observed at thicknesses 15, 20, 30, 50, 70, and 100nm. The observation of the quantum Hall effect at thickness more than 50nm strongly suggests the existence of two-dimensional electron gas in the InAs0.1Sb0.9 layer sandwiched between Al0.1In0.9Sb layers.