Figure 7
From: Atomic-resolved depth profile of strain and cation intermixing around LaAlO3/SrTiO3 interfaces
Profiles obtained from MEIS data in blocking mode.
The x coordinates locate the cations by the number of unit cells to the interface (+1 = first u.c. in STO, −1 = first u.c. in 
). Each data point indicates the distance separating this cation to the A cation located in the above cell. (a–c) Profiles of c/a for samples with film thicknesses of (a) 3 u.c. (c) 5 u.c. Purple circles represent the c/a values around La atoms. Green circles represent the c/a values around Sr atoms. Red squares represent the theoretical c/a values for intermixed heterostructure assuming a sole elastic epitaxial strain. Relaxed cell parameters in this intermixed region were determined from their respective chemical profile obtained experimentally by MEIS random mode. The turquoise dash-dotted line indicates the theoretical c/a value for a fully epitaxial growth of LAO, (aSTO = aLAO) and without intermixing. (b–d) Difference between the c/a values measured experimentally - from He+ scattered from Sr and La atoms - and those calculated from epitaxial strain are plotted for the (b) 3 u.c. sample (d) 5 u.c. sample.
