A team of physicists at the University of Basel have developed a novel structure by layering graphene and molybdenum disulfide (MoS2) that is capable of absorbing nearly all light in a selected wavelength, according to Phys.org. It’s hoped their discovery can be used for certain optical components, or even a source of individual photons.
Such layers of two-dimensional materials like graphene and MoS2 are held together thanks to the van der Waals forces. How the different layers interact can result in entirely new materials with new, sometimes unexpected properties.
“If we apply a voltage to the outer graphene layers, this generates an electric field that affects the absorption properties of the two molybdenum disulfide layers,” says Nadine Leisgang, a lead author of the study. “By adjusting the voltage applied, we can select the wavelengths at which the electron-hole pairs are formed in these layers.”
Richard Warburton adds, “This research could pave the way for a new approach to developing optoelectronic devices such as modulators.”
Modulators can selectively augment a signal’s amplitude. It could also allow the generation of individual photons, with potentially huge implications for the advancement of quantum technology.