TY  - JOUR
AU  - Despoja, Vito
AU  - Radović, Ivan
AU  - Karbunar, Lazar
AU  - Kalinić, Ana
AU  - Mišković, Zoran L.
PY  - 2019
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8595
AB  - We study the wake potential produced by an external charged particle that moves parallel to various sy1-Al2O3-sy2 sandwich-like composites, where the system syi (with i=1,2) may be vacuum, pristine graphene, or doped graphene. The effective dielectric function of the composites is obtained using three complementary methods for graphene's electronic response, based on the massless Dirac fermions (MDF) method, the extended hydrodynamic (eHD) model, and the ab initio approach. Three velocity regimes are explored with respect to the threshold for excitations of the Dirac plasmon in graphene, given by its Fermi velocity vF. In the low-velocity regime (below vF), only the transverse optical (TO) phonons in the Al2O3 layer contribute to the wake potential in the surface with sy2 (which is nearest to the charged particle), in a manner that is only sensitive to the composition of that system: if sy2 is vacuum, the TO phonons give rise to intense oscillations in the wake potential, which are strongly suppressed if sy2 is pristine or doped graphene. For intermediate velocities (above vF), the hybridized plasmon-TO phonon modes on both surfaces contribute to the wake potential in the surface with sy2, with the most dominant contribution coming from the hybridized Dirac-like plasmonic modes. In the high-velocity regime (well above vF), the highest-lying hybridized Dirac plasmon gives the dominant contribution to the wake potential, which exhibits a typical V-shaped wave-front pattern that lags behind the charged particle. It is found that the MDF method agrees very well with the results of the ab initio method for small and intermediate velocities. However, in the high-velocity regime, the high-energy π plasmon in graphene introduces new features in the wake potential in the form of fast oscillations, just behind the charged particle. Those oscillations in the wake potential are well described by both the eHD and the ab initio method, proving that the π plasmon indeed behaves as a collective mode.
T2  - Physical Review B
T1  - Wake potential in graphene-insulator-graphene composite systems
VL  - 100
IS  - 3
SP  - 035443
DO  - 10.1103/PhysRevB.100.035443
ER  - 

@article{
author = "Despoja, Vito and Radović, Ivan and Karbunar, Lazar and Kalinić, Ana and Mišković, Zoran L.",
year = "2019",
abstract = "We study the wake potential produced by an external charged particle that moves parallel to various sy1-Al2O3-sy2 sandwich-like composites, where the system syi (with i=1,2) may be vacuum, pristine graphene, or doped graphene. The effective dielectric function of the composites is obtained using three complementary methods for graphene's electronic response, based on the massless Dirac fermions (MDF) method, the extended hydrodynamic (eHD) model, and the ab initio approach. Three velocity regimes are explored with respect to the threshold for excitations of the Dirac plasmon in graphene, given by its Fermi velocity vF. In the low-velocity regime (below vF), only the transverse optical (TO) phonons in the Al2O3 layer contribute to the wake potential in the surface with sy2 (which is nearest to the charged particle), in a manner that is only sensitive to the composition of that system: if sy2 is vacuum, the TO phonons give rise to intense oscillations in the wake potential, which are strongly suppressed if sy2 is pristine or doped graphene. For intermediate velocities (above vF), the hybridized plasmon-TO phonon modes on both surfaces contribute to the wake potential in the surface with sy2, with the most dominant contribution coming from the hybridized Dirac-like plasmonic modes. In the high-velocity regime (well above vF), the highest-lying hybridized Dirac plasmon gives the dominant contribution to the wake potential, which exhibits a typical V-shaped wave-front pattern that lags behind the charged particle. It is found that the MDF method agrees very well with the results of the ab initio method for small and intermediate velocities. However, in the high-velocity regime, the high-energy π plasmon in graphene introduces new features in the wake potential in the form of fast oscillations, just behind the charged particle. Those oscillations in the wake potential are well described by both the eHD and the ab initio method, proving that the π plasmon indeed behaves as a collective mode.",
journal = "Physical Review B",
title = "Wake potential in graphene-insulator-graphene composite systems",
volume = "100",
number = "3",
pages = "035443",
doi = "10.1103/PhysRevB.100.035443"
}

Despoja, V., Radović, I., Karbunar, L., Kalinić, A.,& Mišković, Z. L.. (2019). Wake potential in graphene-insulator-graphene composite systems. in Physical Review B, 100(3), 035443.
https://doi.org/10.1103/PhysRevB.100.035443

Despoja V, Radović I, Karbunar L, Kalinić A, Mišković ZL. Wake potential in graphene-insulator-graphene composite systems. in Physical Review B. 2019;100(3):035443.
doi:10.1103/PhysRevB.100.035443 .

Despoja, Vito, Radović, Ivan, Karbunar, Lazar, Kalinić, Ana, Mišković, Zoran L., "Wake potential in graphene-insulator-graphene composite systems" in Physical Review B, 100, no. 3 (2019):035443,
https://doi.org/10.1103/PhysRevB.100.035443 . .