A new hybridized plasmon-phonon polariton mode in graphene/h-BN van der Waals heterostructures is presented, featuring the ultrahigh field confinement characteristic of the graphene plasmon and the long lifetime property of the h-BN transverse optical phonon. This enables an ultralong hybrid plasmon lifetime of up to 1.6 ps (with ultrahigh mode confinement up to >l0 2/7000 and ultrasmall group velocity down to 0.001c, where c is the speed of light in vacuum), superior to any localized plasmon ever demonstrated.
- Monolayer h-BN
- Plasmon-phonon polaritons
- Van der Waals heterostructures