Photonic transport in a graphene van der Waals homojunction

Layered structures of two-dimensional (2D) materials stacked by van der Waals interactions such as homojunctions and heterojunctions have shown a number of microelectronic applications in the realm of ultrathin and highly flexible devices. Since van der Waals interaction is the dominant strength among these layered structures and can induce the anisotropic behavior of incident electromagnetic waves or photons, a novel concept of photonic transport can be proposed based on the physical picture of transferring both far-field and near-field components of an object to a certain distance and rebuilding a subwavelength image. Herein, through delicately designing and engineering the layered structures based on graphene, we have achieved a flexible graphene van der Waals homojunction for subwavelength imaging. Such an approach is the first time an optical lens from the atomic level has been designed and constitutes a further important step towards practical applications of subwavelength imaging.