Shubnikov de Hass oscillation in Two-dimensional electron liquid at (111) oriented SrTiO₃ interfaces

Two-dimensional electron liquid (2DEL) at SrTiO₃ surfaces and interfaces have attracted much attention due to their fascinating exotic properties. Most of the studies reported so far have been conducted on the (001) orientation. We created two-dimensional electron liquids in SrTiO3 (111) orientation. Hall measurements reveal a high mobility up to 20000 cm^2/V*s and a carrier concentration of 3*10^14/cm^2. We were able to control the dimensionality based on the band engineering approach and systematically measured the Shubnikov de Hass oscillation (SdH) oscillations at different filling levels. The carrier density was controlled by a gating sequence when difference carrier concentration states can be created with no gate voltage on (no applied electric fields) during the measurements. We observed very pronounced resistance quantum oscillation at low temperatures and magnetic fields up to 9 T. We conducted fast Fourier Transformation (FFT) of the oscillations which revealed the information on the Fermi surface and the filling of the multiple bands. We will discuss the results on the comparison of the near 3D to 2D systems with different band filling levels.