摘要:
Two-dimensional photonic crystal surface-emitting laser comprising a two-dimensional photonic crystal, having media different in refractive index arrayed in a two-dimensional cycle, disposed in the vicinity of an active layer that emits light by the injection of carriers, wherein the two-dimensional photonic crystal consists of square lattices having equal lattice constants in perpendicular directions, and a basic lattice consisting of a square with one medium as a vertex has an asymmetric refractive index distribution with respect to either one of the two diagonals of the basic lattice to thereby emit light in a constant polarizing direction.
摘要:
A two-dimensional photonic crystal surface-emitting laser having a photonic crystal (20) in which a photonic crystal periodic structure (21) is located in or near an active layer (first medium) (12) which emits light when carriers are injected thereto. The photonic crystal periodic structure (21) comprises a second medium with a refractive index different from that of the active layer scattered in two-dimensional periodic array. The photonic crystal periodic structure is of a square lattice structure or a triangular lattice structure which has translation symmetry but does not have rotation symmetry. Alternatively, the phtonic crystal periodic structure is of a square lattice structure or a rectangular lattice structure which is classified into pl, pm, pg or cm according to the two-dimensional pattern classification method. It is the most desirable that the lattice structure is composed of triangular lattice points.
摘要:
A solar cell (1) of the present invention includes a photoelectric conversion layer (2) and a photonic crystal provided inside the photoelectric conversion layer (2) in order to have a photonic band gap. The photonic crystal has defects (31) in order to provide a defect level in the photonic band gap. QV which is a Q value representing a magnitude of a resonance effect yielded by coupling between the photonic crystal and an outside is substantially equal to Qα which is a Q value representing a magnitude of a resonance effect yielded by a medium of the photoelectric conversion layer (2).
摘要:
A plasma etching method capable of oblique etching with a high aspect ratio and high uniformity is provided. In the plasma etching method, a base body is etched with a high aspect ratio by the following process: An electric-field control device having an ion-introducing orifice penetrating therethrough in a direction inclined from the normal to the surface of a base body is placed on or above the surface of this base body. Plasma is generated on the surface of the base body on or above which the electric-field control is placed. A potential difference is formed between the plasma and the base body so as to attract ions in the plasma toward the base body.
摘要:
In conventional organic EL light-emitting devices, the ITO used for a transparent electrode has a refractive index of about 2.0 larger than the refractive index of 1.5 of a transparent glass substrate. As a result, the mode of most of light traveling from the transparent electrode toward the glass substrate is the transparent electrode guided mode, and no light is emitted from the transparent electrode toward the glass substrate. According to the invention, the light extraction efficiency of conventional light-emitting devices such as organic EL light-emitting devices is improved by using mode conversion means so as to solve the problem that conventional light-emitting devices such as organic EL light-emitting devices have low light extraction efficiencies. A light-emitting device of the invention comprises a light-emitting layer on a substrate and mode conversion means for converting the mode from the guided mode into an emission mode. The mode conversion means is provided in the substrate, in the light-emitting layer, or at the interface between the substrate and the light-emitting layer.
摘要:
A semiconductor surface light-emitting element of this invention is provided with a photonic crystal layer 6 obtained by periodically forming a plurality of holes H in a basic layer 6A comprised of a first compound semiconductor of the zinc blend structure and growing embedded regions 6B comprised of a second compound semiconductor of the zinc blend structure, in the holes H, and an active layer 4 to supply light to the photonic crystal layer 6, in which a principal surface of the basic layer 6A is a (001) plane and in which side faces of each hole H have at least three different {100} facets.
摘要:
A plasma etching method capable of oblique etching with a high aspect ratio and high uniformity is provided. In the plasma etching method, a base body is etched with a high aspect ratio by the following process: An electric-field control device having an ion-introducing orifice penetrating therethrough in a direction inclined from the normal to the surface of a base body is placed on or above the surface of this base body. Plasma is generated on the surface of the base body on or above which the electric-field control is placed. A potential difference is formed between the plasma and the base body so as to attract ions in the plasma toward the base body.
摘要:
An objective of the present invention is to provide a surface emitting laser capable of selectively generating a laser oscillation in the fundamental mode and thereby emitting a single-wavelength laser light. In a surface emitting laser including an active layer and a two-dimensional photonic crystal provided on one side of the active layer, a reflector 45 or 46 is provided at least at a portion of the circumference of the two-dimensional photonic crystal. The reflector has a reflectance distribution in which the reflectance has a maximum value at a position where the amplitude envelope of the fundamental mode of an internal resonance light created within the two-dimensional photonic crystal. This design strengthens the fundamental mode while suppressing the second mode, thus enabling the laser oscillation in the fundamental mode to be selectively obtained, so that a single-wavelength laser light can be emitted.
摘要:
The present invention provides an optical multiplexer/demultiplexer that can be smaller in size and higher in Q-factor or efficiency. This object is achieved by the following construction. In a slab-shaped body 11, low refractive index areas 12 having a refractive index lower than that of the material of the body 11 are periodically arranged to construct a two-dimensional photonic crystal, in which a waveguide 13 is formed by not boring holes 12 linearly. A donor type cluster defect 14 is formed by not boring holes 12 at two ore more lattice points located adjacent to the waveguide 13. With this construction, only a specific wavelength of light included in the light propagating through the waveguide 13 resonates at the donor type cluster 14, and the light thus trapped is released to the outside (demultiplexing). Conversely, only a specific wavelength of light may be introduced through the donor type cluster defect 14 into the waveguide 13 (multiplexing).
摘要:
In an optical device, a slab layer includes an active layer sandwiched between cladding layers. The slab layer has a periodic refractive index profile structure in a two-dimensional plane, as a two-dimensional slab photonic crystal structure, and a linear defect region serving as a waveguide in the periodic refractive index profile structure. Regions having different widths of the waveguides, as segments of the waveguide, are connected in series.