Disclosed are dielectric cavity arrays with cavities formed by pairs of dielectric tips, wherein the cavities have low mode volume (e.g., 7*10.sup.−5λ.sup.3, where X is the resonance wavelength of the cavity array), and large quality factor Q (e.g., 10.sup.6 or more). Applications for such dielectric cavity arrays include, but are not limited to, Raman spectroscopy, second harmonic generation, optical signal detection, microwave-to-optical transduction, and as light emitting devices.

Disclosed are dielectric cavity arrays with cavities formed by pairs of dielectric tips, wherein the cavities have low mode volume (e.g., 7*10.sup.−5λ.sup.3, where X is the resonance wavelength of the cavity array), and large quality factor Q (e.g., 10.sup.6 or more). Applications for such dielectric cavity arrays include, but are not limited to, Raman spectroscopy, second harmonic generation, optical signal detection, microwave-to-optical transduction, and as light emitting devices.

A photonic crystal surface-emitting laser includes a substrate, an n-type cladding layer, an active layer, an index matching layer and a photonic crystal structure. The n-type cladding layer is disposed over the substrate. The active layer is disposed over the n-type cladding layer. The index matching layer is disposed over the n-type cladding layer and is arranged around the active layer. The index matching layer is electrically insulating, and an effective refractive index of the index matching layer is substantially identical to an effective refractive index of the active layer. The photonic crystal structure is disposed over the active layer and the index matching layer.

A photonic crystal surface-emitting laser includes a substrate, an n-type cladding layer, an active layer, an index matching layer and a photonic crystal structure. The n-type cladding layer is disposed over the substrate. The active layer is disposed over the n-type cladding layer. The index matching layer is disposed over the n-type cladding layer and is arranged around the active layer. The index matching layer is electrically insulating, and an effective refractive index of the index matching layer is substantially identical to an effective refractive index of the active layer. The photonic crystal structure is disposed over the active layer and the index matching layer.

Provided is a semiconductor laser device including a plurality of semiconductor laser units LDC that are capable of being independently driven, and a spatial light modulator SLM that is optically coupled to a group of the plurality of semiconductor laser units LDC. Each of the semiconductor laser units includes a pair of clad layers having an active layer 4 interposed therebetween, and a diffractive lattice layer 6 that is optically coupled to the active layer 4. The semiconductor laser device includes a ¼ wavelength plate 26 that is disposed between a group of the active layers 4 of the plurality of semiconductor laser units LDC and a reflection film 23, and a polarizing plate 27 that is disposed between the group of the active layers 4 of the plurality of semiconductor laser units LDC and a light emitting surface.

A laser source includes a topological cavity for nonreciprocal lasing, a magnetic material and an optical waveguide. The magnetic material is arranged to interact with the topological cavity. The optical waveguide is arranged to receive light extracted from the topological cavity upon breaking of time-reversal symmetry in the topological cavity.

A light emitting device includes a substrate, a laminated structure provided to the substrate, and including a plurality of columnar parts, and an electrode disposed at an opposite side to the substrate of the laminated structure, wherein the columnar parts have a light emitting layer, the columnar parts are disposed between the electrode and the substrate, light generated in the light emitting layer propagates through the plurality of columnar parts to cause laser oscillation, and the electrode is provided with a hole.

A semiconductor device is provided, which includes a substrate, a first semiconductor structure, a plurality of first holes, a first dielectric structure and a second semiconductor structure. The first semiconductor structure is located on the substrate. The first holes are periodically arranged in the first semiconductor structure. The first dielectric structure is filled in one or more of the first holes. The second semiconductor structure is located on the first semiconductor structure.

A surface-emitting semiconductor light-emitting device includes a first semiconductor layers, an active layer on the first semiconductor layer, a photonic crystal layer on the active layer and a second semiconductor layer on the photonic crystal layer. The photonic crystal layer include first protrusions in a first region and second protrusions in a second region. A spacing of adjacent first protrusions is greater than a spacing of adjacent second protrusions. The second semiconductor layer includes a first layer and a second layer on the first layer. The first layer covers first and second protrusions so that a first space remains between the adjacent first protrusions. The first layer includes a first portion provided between the adjacent second protrusions. The second layer includes a second portion provided between the adjacent first protrusions. The first space between the adjacent first protrusions is filled with the second portion of the second layer.

A surface-emitting semiconductor light-emitting device includes a first semiconductor layers, an active layer on the first semiconductor layer, a photonic crystal layer on the active layer and a second semiconductor layer on the photonic crystal layer. The photonic crystal layer include first protrusions in a first region and second protrusions in a second region. A spacing of adjacent first protrusions is greater than a spacing of adjacent second protrusions. The second semiconductor layer includes a first layer and a second layer on the first layer. The first layer covers first and second protrusions so that a first space remains between the adjacent first protrusions. The first layer includes a first portion provided between the adjacent second protrusions. The second layer includes a second portion provided between the adjacent first protrusions. The first space between the adjacent first protrusions is filled with the second portion of the second layer.