High room temperature mobility in Al2O3/SrTiO3 heterostructures K. H. Gao, X. R. Ma, Q. L. Li, X. H. Zhang, J. P. Xu, Y. Sun and G. Yu EPL, 138 6 (2022) 66003 Published online: 07 July 2022 DOI: 10.1209/0295-5075/ac74dd