Two-dimensional photonic-crystal laser

A two-dimensional photonic-crystal laser formed by sandwiching, between a first electrode and a second electrode, a layered body including an active layer and a two-dimensional photonic-crystal layer in which modified refractive index areas having a refractive index different from a refractive index of a plate-shaped base body are arranged two-dimensionally on the base body, wherein

• the first electrode is divided into a plurality of partial electrodes,
• the second electrode is a frame-shaped electrode including a frame-shaped portion made of a conductor, the second electrode having a window portion which is a space inside the frame-shaped portion being arranged to face a region enclosing the plurality of partial electrodes,
• in the two-dimensional photonic-crystal layer, each of the modified refractive index areas is arranged by being modulated by a predetermined modulation phase Ψ at each lattice point of a basic two-dimensional lattice having periodicity determined so as to form a resonance state with a wavelength λL by forming a two-dimensional standing wave and not to emit light with the wavelength λL to outside, and
• the modulation phase Ψ is expressed by Ψ=r↑·G′↑ using a wavevector k↑=(kx, ky) of light having the wavelength λL in the two-dimensional photonic-crystal layer, an effective refractive index neff of the two-dimensional photonic-crystal layer, a predetermined angle θ, a reciprocal lattice vector G′↑=(g′x, g′y)=(kx±|k↑|(sin θ cos ϕ)/neff, ky±|k↑|(sin θ sin ϕ)/neff) expressed using an azimuth angle ϕ from a predetermined reference line of the basic two-dimensional lattice, and a position vector r↑ of each lattice point, and the angle θ differs depending on a position in the two-dimensional photonic-crystal layer.