Unconventional Surface Plasmon Excitations in Bi 2 Se 3

The investigation of surface plasmon excitations has recently become a field of research due to their high potential to be applicable in sensors, information technologies, cancer research etc. These coherent delocalized electron oscillations are common at metal-dielectric interfaces. However, they also exist in highly doped semiconductors, conducting oxide system or graphene, i.e. in many other systems with high carrier mobility. This poses the question whether such resonances can also be observed at the insulator interfaces.