TY - JOUR
T1 - Unveiling radial breathing mode in a particle-on-mirror plasmonic nanocavity
AU - Wang, Qifa
AU - Li, Chenyang
AU - Hou, Liping
AU - Zhang, Hanmou
AU - Gan, Xuetao
AU - Liu, Kaihui
AU - Premaratne, Malin
AU - Xiao, Fajun
AU - Zhao, Jianlin
N1 - Publisher Copyright:
© 2021 Qifa Wang et al., published by De Gruyter, Berlin/Boston.
PY - 2022/1/3
Y1 - 2022/1/3
N2 - Plasmonic radial breathing mode (RBM), featured with radially oscillating charge density, arises from the surface plasmon waves confined in the flat nanoparticles. The zero net dipole moment endows the RBM with an extremely low radiation yet a remarkable intense local field. On the other hand, owing to the dark mode nature, the RBMs routinely escape from the optical measurements, severely preventing their applications in optoelectronics and nanophotonics. Here, we experimentally demonstrate the existence of RBM in a hexagonal Au nanoplate-on-mirror nanocavity using a far-field linear-polarized light source. The polarization-resolved scattering measurements cooperated with the full-wave simulations elucidate that the RBM originates from the standing plasmon waves residing in the Au nanoplate. Further numerical analysis shows the RBM possesses the remarkable capability of local field enhancement over the other dark modes in the same nanocavity. Moreover, the RBM is sensitive to the gap and nanoplate size of the nanocavity, providing a straightforward way to tailor the wavelength of RBM from the visible to near-infrared region. Our approach provides a facile optical path to access to the plasmonic RBMs and may open up a new route to explore the intriguing applications of RBM, including surface-enhanced Raman scattering, enhanced nonlinear effects, nanolasers, biological and chemical sensing.
AB - Plasmonic radial breathing mode (RBM), featured with radially oscillating charge density, arises from the surface plasmon waves confined in the flat nanoparticles. The zero net dipole moment endows the RBM with an extremely low radiation yet a remarkable intense local field. On the other hand, owing to the dark mode nature, the RBMs routinely escape from the optical measurements, severely preventing their applications in optoelectronics and nanophotonics. Here, we experimentally demonstrate the existence of RBM in a hexagonal Au nanoplate-on-mirror nanocavity using a far-field linear-polarized light source. The polarization-resolved scattering measurements cooperated with the full-wave simulations elucidate that the RBM originates from the standing plasmon waves residing in the Au nanoplate. Further numerical analysis shows the RBM possesses the remarkable capability of local field enhancement over the other dark modes in the same nanocavity. Moreover, the RBM is sensitive to the gap and nanoplate size of the nanocavity, providing a straightforward way to tailor the wavelength of RBM from the visible to near-infrared region. Our approach provides a facile optical path to access to the plasmonic RBMs and may open up a new route to explore the intriguing applications of RBM, including surface-enhanced Raman scattering, enhanced nonlinear effects, nanolasers, biological and chemical sensing.
KW - dark mode
KW - nanoparticles
KW - plasmonic nanocavity
KW - radial breathing mode
UR - http://www.scopus.com/inward/record.url?scp=85122625161&partnerID=8YFLogxK
U2 - 10.1515/nanoph-2021-0506
DO - 10.1515/nanoph-2021-0506
M3 - 文章
AN - SCOPUS:85122625161
SN - 2192-8614
VL - 11
SP - 487
EP - 494
JO - Nanophotonics
JF - Nanophotonics
IS - 3
ER -