Highly tunable, polarization-engineered two-dimensional electron gas in e-AlGaO3/e-Ga2O3 heterostructures

We report on the modeling of polarization-induced two-dimensional electron gas (2DEG) formation at e-AlGaO3/e-Ga2O3 heterointerface and the effect of spontaneous polarization (P-sp) reversal on 2DEG density in e-Ga2O3/e-AlGaO3/e-Ga2O3 double heterostructures. Density-functional theory (DFT) is utilized to calculate the material properties of e-Ga2O3 and e-AlGaO3 alloys. Using Schrodinger-Poisson solver along with DFT calculated parameters, the 2DEG density is calculated as a function of barrier type and thickness. By optimizing the layer thicknesses of e-Ga2O3/e-AlGaO3/e-Ga2O3 heterostructures, charge contrast ratios exceeding 1600 are obtained. This computational study indicates the high potential for e-Ga2O3-based heterostructure devices for non-volatile memories and neuromorphic applications.