Abstract: A chalcogen film is applied to an acute tip of a glass fiber and the acute tip is held in physical contact with a metal layer so as to induce diffusional reaction for generation of a metal chalcogenide nano-particle or nano-particles at the acute tip. In the case where the chalcogen film is directly applied to the acute tip, the generated nano-particle or nano-particles are transferred from the acute tip to a corresponding part of the metal layer. When a silane-adsorbed film is pre-formed on the acute tip before application of the chalcogen film, the generated nano-particle or nano-particles are fixed to the acute tip. The nano-particles are several to tens in number with very narrow distribution of particle size. Since particle size and fixed position of the nano-particle or nano-particles can be controlled with high freedom, the nano-particle or nano-particles are useful as a light-emitting or photo-detecting element.

Abstract: A newly proposed element for fluorescence analysis has a metallic nano-well 3, which has a bottom modified with an active group or detecting DNA, formed in a metal film 2 deposited on a substrate. A fluorescence reagent is bonded to an antigen coupled with the active group or to objective DNA hybridized with the detecting DNA. Fluorescence is efficiently emitted from the fluorescence reagent by photo-excitation without discoloration.

Abstract: After a chalcogen film 3 is applied to an acute tip 2 of a glass fiber 1, the acute tip 2 is held in physical contact with a metal layer 5 so as to induce diffusional reaction for generation of a metal chalcogenide nano-particle or nano-particles 6 at the acute tip 2. In the case where the chalcogen film 3 is directly applied to the acute tip 2, the generated nano-particle or nano-particles 6 are transferred from the acute tip 2 to a corresponding part of the metal layer 5. When a silane-adsorbed film 4 is pre-formed on the acute tip 2 before application of the chalcogen film 3, the generated nano-particle or nano-particles 6 are fixed to the acute tip 2. The nano-particles 6 are several to tens in number with very narrow distribution of particle size. Since particle size and fixed position of the nano-particle or nano-particles 6 can be controlled with high freedom, the nano-particle or nano-particles 6 are useful as a light-emitting or photo-detecting element.

Abstract: A photoresponsive electrode for a wet solar cell wherein on a metal film having fixed thereon a photoresponsive molecule such as, for example, a porphyrin derivative, there is fixed by vapor deposition a light-irradiating portion such as a prism or optical fibers, and the metal film is irradiated with a light via the light-irradiating portion at about the resonance incident angle .theta. of inducing surface plasmon resonance in the interface between the metal film and the light-irradiating portion, and a wet solar cell using the photoresponsive electrode. In the photoresponsive electrode, the reflection of the incident light at the metal film can be restrained and the photoresponsive molecule can be efficiently excited even by sunlight of a low energy and the wet solar cell has a very excellent photoelectric transformation efficiency.