Due to the coexistence of many emergent phenomena, including 2D superconductivity and a large Rashba spin‐orbit coupling, 5d transition metal oxides‐based two‐dimensional electron systems (2DESs) have been prospected as one of the potential intrants for modern electronics. However, despite the lighter electron mass, the mobility of carriers, a key requisite for high‐performance devices, in 5d‐oxides devices remains far behind their 3d‐oxides analogs. The carriers’ mobility in these oxides is significantly hampered by the inevitable presence of defects. Here, very high mobility (≈22 650 cm2V−1s−1) of 5d‐2DES confined at the LaAlO3/KTaO3interface is reported. The high mobility, which is beyond the values observed in SrTiO32DESs in the same carrier‐density range, is achieved using the ionic‐liquid gating at room temperature. The authors postulate that the ionic‐liquid gating affects the oxygen vacancies and efficiently reduces any disorder at the interface. Investigating density and mobility in a broad range of back‐gate voltage, the authors reveal that the mobility follows the power‐law
This content will become publicly available on May 1, 2024
- NSF-PAR ID:
- 10415494
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 122
- Issue:
- 18
- ISSN:
- 0003-6951
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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