Largely Enhanced Mobility in Trilayered LaAlO/SrTiO/LaAlO Heterostructures.

LaAlO (LAO)/SrTiO (STO)/LaAlO (LAO) heterostructures were epitaxially deposited on TiO-terminated (100) SrTiO single-crystal substrates by laser molecular beam epitaxy. The electron Hall mobility of 1.2 × 10 cm/V s at 2 K was obtained in our trilayered heterostructures grown under 1 × 10 Torr, which was significantly higher than that in single-layer 5 unit cells LAO (∼4 × 10 cm/V s) epitaxially grown on (100) STO substrates under the same conditions.