Observation of the interfacial-field-induced weak antilocalization in InAs quantum structures

We have studied low-temperature magnetoconductance and observed weak antilocalization in an AlSb/InAs/AlSb quantum-well structure. The spin-orbital field deduced from the antilocalization data is found to be insensitive to photoinduced changes in the carrier density, suggesting that the interfacial-field-induced rather than the crystal-field-induced spin splitting is the predominant cause of the spin-orbital scattering. We also find a significant enhancement of spin-orbital scattering in ZnTe/InAs/AlSb structures which can be explained by the structural asymmetry, thereby confirming the dominant role of the interfacial field.