arXiv subjects

Stephen Arnold

Publications and source records attributed to Stephen Arnold.

2 recordsLinked to original sources

arXiv2026

Influence of metal nanoparticles on whispering gallery modes of a microcavity

Photonic microcavities offer high energy density and low mode volume and attract special attention due to wide range of applications. Subsequent developments in the area of plasmonic nanocavities have also opened up applications despite their high absorptive properties. In the last two decades, photonic-plasmonic hybrid microcavities have been investigated extensively. In this article, we have conducted a review of the literature on photonic and plasmonic systems individually as well as in hybrid systems. Along with the underlying physics, applications such as cavity quantum electrodynamics, lasing, sensing, nonlinear optics and Raman spectroscopy have been reviewed. The outputs of the systems for each applications have been discussed and compared for photonic and hybrid systems. This review will provide a thorough understanding of the effects of optical cavities and plasmonics and their applications.

physics.optics↗

arXiv2016

Whispering gallery mode single nano-particle detection and sizing: the validity of the dipole approximation

Interactions between whispering gallery modes (WGMs) and small nanoparticles are commonly modelled by treating the particle as a point dipole scatterer. This approach is assumed to be accurate as long as the nanoparticle radius, $a$, is small compared to the WGM wavelength $λ$. In this article, however, we show that the large field gradients associated with the evanescent decay of a WGM causes the dipole theory to significantly underestimate the interaction strength, and hence induced WGM resonance shift, even for particles as small as $a\sim λ/10$. To mitigate this issue we employ a renormalized Born approximation to more accurately determine nanoparticle induced resonance shifts and hence enable improved particle sizing. The domain of validity of this approximation is investigated and supporting experimental results are presented.

physics.optics↗