Modulation of the electromagnetic local density of states in graphene-based hyperbolic metamaterials

Abstract

We theoretically investigate the electromagnetic local density of states (EM-LDOS) within the proximity of graphene-based hyperbolic metamaterials (HMM) that are alternately stacked with graphene and silicon carbide (SiC) by using effective medium theory (EMT). Compared with that in graphene-covered SiC bulk, two broad bands appear in the EM-LDOS spectrum because of the occurrence of hyperbolic modes in HMM. EM-LDOS can be tuned by the chemical potential of graphene and the thickness of SiC. It can be exactly calculated using the transfer matrix method (TMM). We show that the results obtained using TMM are consistent with those obtained using EMT when the distance from HMM is larger than the thickness of SiC. When the width of SiC is sufficiently thick, EM-LDOS is equivalent to that of graphene-covered SiC bulk.