Advanced Optical Materials

S. Hirata, C. Adachi, and co-workers demonstrate thermoreversible media using timedependent, persistent room temperature phosphorescence. On page 438, aggregation changes to persistent phosphorescent guest molecules within a hydroxyl steroidal host, controlled by thermal hysteresis, trigger the reversible on–off recording of persistent room temperature phosphorescence.

On page 422, dye molecular doping of an organic semiconductor single crystal enables H. Nakanotani and C. Adachi to tune its light amplification characteristics, significantly reducing the amplified spontaneous emission threshold via an enhancement of the photoluminescence quantum efficiency. The dye-doped organic semiconductor crystal maintains high ambipolar carrier mobilities and shows bright, self-waveguided emission from the crystal edge under both optical and electrical excitation.

Coaxial microcavities etched into the surface of a heavily-doped silicon substrate by W. Withayachumnankul, S. Sriram, and co-workers are shown on page 443 to support localized surface plasmon resonances at terahertz frequencies through the interplay between the cylindrical surface plasmon polaritons and the cavity modes. The coaxial geometry partly determines the resonance frequency, as illustrated by the absorption map.