Patent ID: 7978745
Filing Date: 2011-07-12
Classification: H01S

Abstract:
1. A two-dimensional photonic crystal surface-emitting laser having a two-dimensional photonic crystal placed near an active layer that emits light when carriers are injected thereinto, the two-dimensional photonic crystal comprising: a first medium having a predetermined refractive index and an array of patches of a second medium, the array of patches of the second medium arrayed inside the first medium, the second medium having a different refractive index from the first medium, wherein all mode degeneration at a Γ point of the two-dimensional photonic crystal is resolved, wherein the patches of the second medium are arrayed at equal intervals in mutually perpendicular first and second directions within the first medium, the array of patches of the second medium thereby forming a square lattice, wherein a fundamental lattice that repeats with a minimum period and having patches of the second medium at the vertices thereof forms the square lattice, and wherein at least in part of the fundamental lattices, the patches of the second medium, as seen in a plan view, are asymmetric with respect to one of two diagonal lines of the corresponding fundamental lattices.