Quantum point contacts on two-dimensional electron gases with a strong spin-orbit coupling*

Studies of electrical transport in one-dimensional semiconductors in a presence of a strong spin-orbit interaction are crucial not only for exploring the emergent phenomena, such as topological superconductivity, but also for potential spintronic applications by controlling of the electron spins. We investigate the electrical transport properties of one-dimensional confinement defined by electrostatic potentials on large area two-dimensional electron gases of InAs and InSb, which have a strong spin-orbit coupling. The high-quality InAs and InSb quantum wells are grown on antimonide buffers by molecular beam epitaxy, and the gate-tunable regions are created using Al$_{\mathrm{2}}$O$_{\mathrm{3}}$ or HfO$_{\mathrm{2}}$ gate dielectrics by atomic layer deposition. We will discuss the modulation of spin-orbit coupling in the two-dimensional electron gases and the spin-orbit-induced spin splitting by the split-gate quantum point contacts.