These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information. For more information, please see our FAQs.
Dev17.pdf (1.14 MB)
Unconventional Optical Response in Engineered Au-Ag Nanostructures
Preprints are manuscripts made publicly available before they have been submitted for formal peer review and publication. They might contain new research findings or data. Preprints can be a draft or final version of an author's research but must not have been accepted for publication at the time of submission.
submitted on 06.06.2019 and posted on 07.06.2019by Dev Kumar Thapa, Subham Kumar Saha, Guru Pratheep Rajasekar, Biswajit Bhattacharyya, Rekha Mahadevu, Anshu Pandey
article describes the optical properties of nanostructures composed of silver
particles embedded into a gold matrix. In previous studies these materials were
shown to exhibit temperature dependent transitions to a highly conductive and
strongly diamagnetic state. Here we describe the anomalous optical properties
of these nanostructures. Most notably, these materials fail to obey Mie theory
and exhibit an unconventional resonance with a maximum at about 4 eV, while the
usual gold and silver localized surface plasmon resonances are suppressed. This
effect implies a significant deviation from the bulk dielectric functions of gold
and silver. We further resolved this resonance into its absorbance and
scattering sub-parts. It is observed that the resonance is largely comprised of
scattering, with negligible losses even at ultraviolet frequencies.