Surface Quantum Wells*

The rising interest into topological superconductors has led to the exploration of hybrid superconductor-semiconductor structures. In these structures two dimensional electron gases are confined near surface and can make epitaxial contact to superconducting thin films. Large Zeeman splitting and spin orbit coupling are necessary ingredients to look for when choosing the semiconductor. Here we present findings of our experiments on two prime candidates with strong spin orbit interaction and high g-factor: InAs and InAs_.5Sb_.5. We measure weak anti-localization signal and integer quantum hall energy gaps as a function of carrier density in near surface quantum wells of both materials. We use fitting of weak anti-localization to determine strength of spin orbit interaction and the energy gaps of odd Integer quantum Hall states (v=3 and v=5) to extract g-factors.