Localized surface plasmon resonance (LSPR) switching was investigated in a Au/GeSbTe/Au nanosandwich as a key active element for plasmonic integrated circuits and devices. Near-infrared single-particle spectroscopy was conducted to examine the interaction of a Au nanorod (AuNR) and Au film, between which a GeSbTe layer was incorporated as an active phase-change media. Numerical calculation revealed that hybridized modes of the AuNR and Au film exhibit a significant change of scattering intensity with the phase change. In particular, the antisymmetric (magnetic resonance) mode can be modulated effectively by the extinction coefficient of GST, as well as its refractive index. Experimental demonstration of the switching operation was performed by alternate irradiation with a picosecond pulsed laser for amorphization and a continuous wave laser for crystallization. Repeatable modulation was obtained by monitoring the scattering light around the LSPR peak at λ = 1070 nm.

The geometric structures of 7-azaindole (7-AzI) and its dimer were investigated by laser-induced fluorescence (LIF). The rotationally resolved LIF spectrum (resolution:-0.00003 cmof 7-AzI monomer shows that (i) rotational constants are A" 0.13082(5), B" 0.05677(2), C" 0.03970(1), A' 0.12468(5), B'= 0.056752(2), and C' 0.03911(1), and (ii) the transition dipole moment direction is tilted at an angle of + 21(5) degrees with respect to a axis. The LIF spectrum (resolution:-0.06 cm-) of the nonreactive 7-AzI dimer suggests there are three possibilities for the geometric structure, having "single bonded", "T-shaped", and "non-planar" structures. The ionization energy of 7-AzI was determined to be 8.1171(5) eV by using pulsed-field ionization photoelectron spectroscopy (PFI-PES). Several vibronic bands of 7-AzI cation were observed and compared with those of neutral 7-AzI in the So and S states. The electron binding energies of 7-AzI cluster anions (2 _< n < 5) were determined by photoelectron spectroscopy.

No abstract

We investigate the modulation of the localized surface plasmon resonance (LSPR) of a gold nanorod (AuNR) using a GeSbTe film as an active medium. We demonstrate high-contrast switching of LSPR in an AuNR/GST/Au thin film sandwich structure upon phase change. To go beyond this single-particle switching functionality, we consider a plasmon particle system interacting with a phase-change material (PCM) to discuss the possibility of parallel processing devices with memory functionality, exploiting the plasticity and threshold behavior that are inherent characteristics of PCMs. We demonstrate that the temporal and spatial evolution of a plasmon-PCM array system can be equivalent to a cellular automata algorithm.

No abstract