Abstract: A device for guiding and absorbing electromagnetic radiation, the device including: absorbing means for absorbing the electromagnetic radiation; and a coupled to the absorbing means for guiding the electromagnetic radiation to the absorbing means, wherein the waveguide and the absorbing means are formed from a structure including a first cladding layer, a second cladding layer over the first cladding layer, and a quantum-well layer between the first and second cladding layers, the quantum-well layer being formed of a material having a different composition to the first and second cladding layers, wherein the thickness and the composition of the quantum-well layer is optimised to provide an acceptable level of absorption of electromagnetic radiation in the waveguide while providing an appropriate band gap for absorption of the electromagnetic radiation in the absorbing means.

Abstract: A device comprising: a substrate; a plurality of resonators on the substrate, each of the resonators of the plurality of resonators being resonant at a predetermined wavelength of electromagnetic radiation and at least some of the resonators being arranged to operate in different resonance orders; a waveguide on the substrate, the waveguide being coupled to the plurality of resonators for guiding the electromagnetic radiation to the plurality of resonators, wherein the resonance order of each resonator along the waveguide is optimized to maximize the coupling of light into the resonators.

Abstract: Methods and kits useful for identifying a pig as producing an increased litter size are provided. Genetic makers, in particular SNP markers are provided that are useful in distinguishing pigs for a phenotype associated with increased litter size.

Abstract: A spectrometer comprises a substrate and a waveguide on the substrate, the waveguide including an elongate part and a tapered input for guiding electromagnetic radiation to the elongate part. The tapered input includes an input end for receiving the electromagnetic radiation and an output end coupled to the elongate part, the input end being wider than the output end. The spectrometer may further comprise a plurality of resonators coupled to the elongate part of the waveguide.

Abstract: A device for detecting electromagnetic radiation comprises a waveguide and at least one resonator on a substrate, and a low-refractive index region between each resonator and the substrate. The low-refractive index region has a lower refractive index than a material of the resonator. The low-refractive index region may be annular, and may have a width corresponding to a width of a region in which electromagnetic radiation is concentrated in a whispering-gallery resonant mode. The low-refractive index region may be an air gap between the substrate and the resonator. The device may be a spectrometer for detecting a plurality of predetermined wavelengths of electromagnetic radiation.

Abstract: A structure for guiding electromagnetic radiation, including: a substrate; a waveguide provided on the substrate and having a first end for receiving electromagnetic radiation and a second end; and an anti-reflection region provided at the second end of the waveguide on the substrate, the length and the width of the anti-reflection region being optimized to suppress back reflection of radiation that reaches the second end.

Abstract: A spectrometer comprises a substrate and a waveguide on the substrate, the waveguide including an elongate part and a tapered input for guiding electromagnetic radiation to the elongate part. The tapered input includes an input end for receiving the electromagnetic radiation and an output end coupled to the elongate part, the input end being wider than the output end. The spectrometer may further comprise a plurality of resonators coupled to the elongate part of the waveguide.

Abstract: A device for detecting electromagnetic radiation comprises a waveguide and at least one resonator on a substrate, and a low-refractive index region between each resonator and the substrate. The low-refractive index region has a lower refractive index than a material of the resonator. The low-refractive index region may be annular, and may have a width corresponding to a width of a region in which electromagnetic radiation is concentrated in a whispering-gallery resonant mode. The low-refractive index region may be an air gap between the substrate and the resonator. The device may be a spectrometer for detecting a plurality of predetermined wavelengths of electromagnetic radiation.

Abstract: A device for guiding and absorbing electromagnetic radiation, the device including: absorbing means for absorbing the electromagnetic radiation; and a coupled to the absorbing means for guiding the electromagnetic radiation to the absorbing means, wherein the waveguide and the absorbing means are formed from a structure including a first cladding layer, a second cladding layer over the first cladding layer, and a quantum-well layer between the first and second cladding layers, the quantum-well layer being formed of a material having a different composition to the first and second cladding layers, wherein the thickness and the composition of the quantum-well layer is optimised to provide an acceptable level of absorption of electromagnetic radiation in the waveguide while providing an appropriate band gap for absorption of the electromagnetic radiation in the absorbing means.

Abstract: A structure for guiding electromagnetic radiation, including: a substrate; a waveguide provided on the substrate and having a first end for receiving electromagnetic radiation and a second end; and an anti-reflection region provided at the second end of the waveguide on the substrate, the length and the width of the anti-reflection region being optimised to suppress back reflection of radiation that reaches the second end.

Abstract: A device comprising: a substrate; a plurality of resonators on the substrate, each of the resonators of the plurality of resonators being resonant at a predetermined wavelength of electromagnetic radiation and at least some of the resonators being arranged to operate in different resonance orders; a waveguide on the substrate, the waveguide being coupled to the plurality of resonators for guiding the electromagnetic radiation to the plurality of resonators, wherein the resonance order of each resonator along the waveguide is optimised to maximise the coupling of light into the resonators.