Graphene, an atomically thin sheet of hexagonally oriented carbon, is a zero-band-gap conductor (semi-metal) that exhibits extraordinary electronic behavior and broadband optical absorption. Hexagonal boron nitride, which shares a similar structure to that of graphene, is a highly insulating electronic material that does not absorb any light in the visible spectrum. By combining graphene and boron nitride into ultrathin vertical stacks, we can fabricate new optoelectronic devices that demonstrate highly sensitive optical response, yet are only as thick as the width of a DNA molecule. In this talk, I will discuss how stacking these atomically thin materials allows us to explore new types of optoelectronic devices that may ultimately lead to more efficient light energy harvesting technologies.