Carrier density dependence of spin–orbit interaction in InAsSb quantum wells

We investigated the spin–orbit interaction (SOI) in Al0.1In0.9Sb/Sn-doped InAs0.1Sb0.9 quantum wells (QWs) with different doping levels using the weak anti-localization effect in the magneto-resistance. The inelastic scattering time is close to the T−1 law predicted theoretically for electron–electron interaction, and the spin–orbit scattering time is temperature independent as expected for the Dʹyakonov–Perel mechanism. The carrier-density dependence of zero-field spin-splitting energy extracted from the fits of magneto-resistance was examined by the theoretical calculation. The result confirms that the Dresselhaus SOI is much larger than the Rashba SOI in our QWs. The dominance of the Dresselhaus term in SOI originates in the large weight factor of InSb-based alloy.