1 research outputs found
Largely Enhanced Mobility in Trilayered LaAlO<sub>3</sub>/SrTiO<sub>3</sub>/LaAlO<sub>3</sub> Heterostructures
LaAlO<sub>3</sub> (LAO)/SrTiO<sub>3</sub> (STO)/LaAlO<sub>3</sub> (LAO) heterostructures were epitaxially deposited on TiO<sub>2</sub>-terminated (100) SrTiO<sub>3</sub> single-crystal substrates
by laser molecular beam epitaxy. The electron Hall mobility of 1.2
× 10<sup>4</sup> cm<sup>2</sup>/V s at 2 K was obtained in our
trilayered heterostructures grown under 1 × 10<sup>–5</sup> Torr, which was significantly higher than that in single-layer 5
unit cells LAO (∼4 × 10<sup>3</sup> cm<sup>2</sup>/V s)
epitaxially grown on (100) STO substrates under the same conditions.
It is believed that the enhancement of dielectric permittivity in
the polar insulating trilayer can screen the electric field, thus
reducing the carrier effective mass of the two-dimensional electron
gas formed at the TiO<sub>2</sub> interfacial layer in the substrate,
resulting in a largely enhanced mobility, as suggested by the first-principle
calculation. Our results will pave the way for designing high-mobility
oxide nanoelectronic devices based on LAO/STO heterostructures