The spatiotemporal dynamics of a surface plasmon polariton (SPP) wave packet (WP) that interacts with a plasmonic nanocavity on a metal surface are investigated via femtosecond time-resolved two-photon fluorescence microscopy and numerical calculations. The nanocavity, which consists of a metal–insulator–metal (MIM) laminar structure (longitudinal length: ∼100 nm), behaves as a subwavelength meta-atom possessing discretized eigenenergies. When a chirp-induced femto-second SPP WP is incident on the nanocavity, only the spectral component matching a particular eigenenergy is transmitted to continue propagation on the metal surface. This spectral clipping induces a spatial peak shift in the WP. The shift can be controlled by tuning the eigenenergy or chirp.

To study the dynamical optical interactions of nano-scaled metal-insulator-metal (MIM) structures in temporal-frequency domain, femtosecond surface plasmon polariton (SPP) wave packets propagate over a surface with a MIM structure. The resonance nature of the SPPcavity interaction is reflected as strong modulations in the spectra of transmitted and reflected SPP wavepackets, which show peaks and valleys, respectively, corresponding to the MIM cavity's eigenmode. These features indicate that the MIM structure acts as a Fabry-Pérot etalontype spectrum filter. With appropriate tuning of the resonance frequency of the cavity, one can extract a wave packet with a narrower time duration and temporally shifted intensity peak.

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The purpose of this study is to clarify the factor of "the visible area", "the recognizable area" and "the non-recognizable area" of the Tokyo Tower from its surrounding streets.locations. The Tokyo Tower street visibility and its relationship between the visible areas and the viewing distance inside a the viewing distance. By contrast, the recognizable areas present an inverse proportional relation to the viewing distance and these areas were found in streets located in the west, north-west and south areas of the Tokyo Tower. The recognizable areas are presented only in particular streets inside 200 meter radio where the recognition of the Tokyo Tower is hardly because is hidden by trees or buildings, but possible due to the top part visibility. Additionally, the recognizable areas were

Analysis of the particle size of metal specimens is important for quality control of metal alloys. In many cases, the EBSD method was used for grain size analysis. However, the EBSD method requires that the specimen be tilted at a signi cant angle. Therefore, we tried to observe the grain size using a new detector under non tilted sample conditions. The detector is a segmented backscattered electron detector that can detect differences in signal intensity due to the EBSD pattern of each segment. The detected signal intensities were compared to obtain the particle shape, and the particle size was measured using this data.