Access to this article is restricted until 12 months after publication by request of the publisher.. Restriction lift date: 2021-07-24
Probing dipole and quadrupole resonance mode in non-plasmonic nanowire using Raman spectroscopy
Kumar Mondal, Prasanna
Holmes, Justin D.
Electric field enhancement in semiconductor nanostructures offers a possibility to find an alternative to the metallic particles which is well known for tuning the light-matter interaction due to its strong polarizability and size-dependent surface plasmon resonance energy. Raman spectroscopy is a powerful technique to monitor the electric field as its scattering depends on the electromagnetic eigenmode of the particle. Here, we observe enhanced polarized Raman scattering from germanium nanowires of different diameters. The incident electromagnetic radiation creates a distribution of the internal electric field inside the naowires which can be enhanced by manipulating the nanowire diameter, the incident electric field and its polarization. Our estimation of the enhancement factor, including its dependence on nanowire diameter, agrees well with the Mie theory for an infinite cylinder. Furthermore, depending on diameter of nanowire and wavelength of incident radiation, polarized Raman study shows dipolar (antenna effect) and quadrupolar resonances, which has never been observed in germanium nanowire. We attempt to understand this polarized Raman behavior using COMSOL Multiphysics simulation, which suggests that the pattern observed is due to photon confinement within the nanowires. Thus, the light scattering direction can be toggled by tuning the polarization of incident excitation and diameter of non plasmonic nanowire.
Single molecule detection , Semiconductor nanowires , Silicon , Scattering , Nanoparticles , Germanium , Phonon , Electric field enhancement , Polarized raman scattering , Dipolar and quadrupolar resonances , Non-plasmonic nanowire
Raha, S., Mitra, S., Kumar Mondal, P., Biswas, S., D Holmes, J. and Singha, A. (2020) 'Probing dipole and quadrupole resonance mode in non-plasmonic nanowire using Raman spectroscopy', Nanotechnology, 31(42), 425201 (6 pp). doi: 10.1088/1361-6528/ab9cf9
© 2020 IOP Publishing Ltd. This is an author-created, un-copyedited version of an article accepted for publication in Nanotechnology. The publisher is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at https://doi.org/10.1088/1361-6528/ab9cf9 As the Version of Record of this article has been published on a subscription basis, this Accepted Manuscript will be available for reuse under a CC BY-NC-ND 3.0 licence after a 12 month embargo period.