Electrical detection of the flat-band position in field-effect van der Waals structures

Flat-band systems of two-dimensional materials have enabled the investigation of emergent quantum phenomena and correlated states in van der Waals heterostructures. However, the electrical detection of the energetic position of van Hove singularities in field-effect structures has been hindered by the critically high effective masses of carriers at flat dispersions. Here, we exploit tunneling mechanisms in heterostructures based on different thicknesses of indium selenide in order to demonstrate the electrical detection of the van Hove singularity position in layer-dependent field-effect structures from cryogenic to room temperature. Our work indicates the study of tunneling currents as a viable approach to investigate the properties of van der Waals flat-band systems.