Growth-induced electron mobility enhancement at the LaAlO3/SrTiO3 interface

We have studied the electronic properties of the 2D electron liquid present at the LaAlO3/SrTiO3 interface in series of samples prepared at different growth temperatures. We observe that interfaces fabricated at 650 degrees C exhibit the highest low temperature mobility (approximate to 10 000 cm(2) V-1 s(-1)) and the lowest sheet carrier density (approximate to 5 x 10(12) cm(-2)). These samples show metallic behavior and Shubnikov-de Haas oscillations in their magnetoresistance. Samples grown at higher temperatures (800- 900 degrees C) display carrier densities in the range of approximate to 2 - 5 x 10(13) cm(-2) and mobilities of approximate to 1000 cm(2) V-1 s(-1) at 4K. Reducing their carrier density by field effect to 8 x 10(12) cm(-2) lowers their mobilities to approximate to 50 cm(2) V-1 s(-1) bringing the conductance to the weak-localization regime. (C) 2015 AIP Publishing LLC.