Strain Switching in van der Waals Heterostructures triggered by a\n Spin-Crossover Metal Organic Framework

Abstract

Van der Waals heterostructures (vdWHs) combine different layered materials\nwith properties of interest,1 such as two-dimensional (2D) semimetals,\nsemiconductors, magnets or superconductors. These heterostructures provide the\npossibility of engineering new materials with emergent functionalities that are\nnot accessible in another way. Beyond inorganic 2D materials, layered molecular\nmaterials remain still rather unexplored, with only few examples regarding\ntheir isolation as atomically thin-layers. By a proper chemical design, the\nphysical properties of these systems can be tuned, as illustrated by the\nso-called spin-crossover (SCO) compounds, in which a spin transition can be\ninduced by applying external stimuli like light, temperature, pressure or an\nelectric field. Here, we report on vdWHs formed by SCO layers and few-layers\ngraphene, being its properties modified by the strain concomitant to the spin\ntransition. These molecular/inorganic vdWHs represent the deterministic\nincorporation of bistable molecular layers with other 2D materials of interest\nin the emergent field of straintronics.\n