In this project, we use lateral force microscopy to investigate how friction of manganite films can be controlled by the properties of the surrounding materials. Specifically, we use phase transformations [1,2] and superlattice thin film samples [3] to actively control the film properties while keeping the surfaces unchanged. \newline
We observed an increase in friction during resistive switching of a La$_{0.55}$Ca$_{0.45}$MnO$_3$ film [1] and during heating of a La$_x$Sr$_{1-x}$MnO$_3$ thin film through the metal-insulator phase transformation [2]. Careful consideration of the different contributions and comparison with literature lead to the conclusion that the electronic contributions are not sufficient to account for our observations and make phononic contributions a promising candidate. \newline
To test our hypothesis, we have recently started to perform measurements on LaMnO$_3$/SrMnO$_3$ superlattice systems in which the propagation of phonons can be actively manipulated by the layer spacing [3], while the morphology of the surface layer remains unchanged.\newline

References
[1] H. Schmidt; J.-O. Krisponeit; N. Weber; K. Samwer; C.A. Volkert; Physical Review Materials, 2020, 4, 113610.
[2] N.A. Weber; H. Schmidt; T. Sievert; C. Jooss; F. Güthoff; V. Moshneaga; K. Samwer; M. Krüger; C.A. Volkert; Advanced Science, 2021, 2003524.
[3] D. Meyer; V. Roddatis; J.P. Bange; S. Lopatin; M. Keunecke; D. Metternich; U. Roß; I.V. Maznichenko; S. Ostanin; I. Mertig; V. Radisch; R. Egoavil; I. Lazić; V. Moshnyaga; H. Ulrichs; arXiv:2009.14532v3, 2020