Rashba splitting of kinetically bound states in gated HgCdTe surface quantum wells

Abstract The Rashba spin–orbit splitting of 2D electron gas in gated HgCdTe surface quantum wells on n -HgCdTe is studied experimentally (by the magneto-capacitance spectroscopy of Landau level method) and theoretically with emphasis on the peculiarities of spectrum at surface densities N s corresponding to the onset of 2D subbands occupancy, where the regime of kinetic binding is realized. Although the spin–orbit splitting in kinetic confinement regime is small, the “Rashba polarization” Δ n / n can achieve 100% because of strong difference in values of cutoff wave vector k c for different spin-split sub-subbands.