Phase Change Memory (PCM) is a key enabling technology for nonvolatile data storage at the nanometer scale. It is a potential candidate to bridge the gap between storage and working memory and may enable in-memory computation in non-Von Neumann architectures. PCM exploits the large resistance contrast between the amorphous and crystalline states in a small active volume of so called phase change materials. In existing devices, the active volume consists of a single layer phase change material. In a recent paper, Ding et al. [Science 366, 210 (2019)] proposed an alternative approach based on a nanolaminated heterostructure, where thin layers of phase change material are interlaced with heat-confining layers. As the phase change in these devices is thermally driven, the control of heat flow at the nanoscale is critical for increasing device performance and improving energy efficiency. In this FWO-SB project, I aim to widen the toolbox of confinement materials used in such heterostructured approaches, and explore how the material choice and properties of the individual layers affect the heat transfer, thermal stability and switching mechanism. To achieve this goal, I will combine combinatorial thin film deposition with in-depth structural, thermal and electrical characteriziation, starting with single layers, and then moving on to bilayers and full multilayer heterostructures.