Yingying Wu
We observe capacitance enhancement in a newly emerged 2D layered material, atomically thin black phosphorus (BP). The encapsulation of BP by hexagonal boron nitride sheets with few-layer graphene as a terminal ensures ultraclean heterostructure interfaces, allowing us to observe negative compressibility at low hole carrier concentrations. We explain the negative compressibility based on the Coulomb correlation among in-plane charges and their image charges in a gate electrode in the framework of Debye screening.
For more information, please refer to our paper: Wu, Yingying, et al. “Negative compressibility in graphene-terminated black phosphorus heterostructures.” Physical Review B 93.3 (2016): 035455. Read More
Negative compressibility has been observed at low hole carrier concentrations.