Abstract: The present disclosure provides a wavelength division multiplexing (WDM) device for demultiplexing an optical signal including a plurality of wavelength channels. The device comprises at least one demultiplexer block configured to provide, for each wavelength channel of the optical signal, two half-channel signals. The device further comprises a mode mapping block configured to map one half-channel signal related to a split wavelength channel into a first polarization mode, and the other half-channel signal related to the same split wavelength channel into a second polarization mode. The device also comprises an output block for each wavelength channel, each output block being configured to combine polarized half-channel signals related to the same wavelength channel.

Abstract: The present disclosure provides a WDM, device 100 for demultiplexing an optical signal 101 including a plurality of N wavelength channels. The device 100 comprises at least one demultiplexer block 102 configured to split the optical signal into two half-channel signals 103 for each wavelength channel. The device 100 further comprises a mode mapping block 104 configured to map one half-channel signal 103 related to a split wavelength channel into a first polarization mode, and the other half-channel signal 103 related to the same split wavelength channel into a second polarization mode. The device 100 also comprises an output block 105 for each wavelength channel, which is configured to combine all polarized half-channel signals related to the same wavelength channel.

Abstract: Disclosed are optical devices for coupling radiation between an optical waveguide and an external medium. In one embodiment, an optical device is disclosed comprising a semiconductor die comprising an integrated optical waveguide core and an overlying optical waveguide comprising a waveguide taper and a waveguide facet. The overlying optical waveguide at least partially overlies the integrated optical waveguide core, and the waveguide facet is between about 1 ?m and 200 ?m from an edge of the semiconductor die. In another embodiment, a method is disclosed comprising providing a substrate comprising an integrated semiconductor waveguide and forming on the substrate an overlying waveguide comprising a waveguide taper and a waveguide facet. The overlying waveguide at least partially overlies the integrated semiconductor waveguide. The method further includes cutting the substrate about 1 ?m and 200 ?m from the waveguide facet.

Abstract: An optical coupler for processing radiation is described. The optical coupler comprises a first deep-shallow waveguide and a second deep-shallow waveguide for guiding radiation in a propagation direction. Each of the deep-shallow waveguides is a waveguide comprising a shallow etched portion and an unetched portion having a width substantially constant along the propagation direction. The width of the shallow etched portion is substantially larger than the width of the unetched portion. The shallow etched portion of the first deep-shallow waveguide and the shallow etched portion of the second deep-shallow waveguide are arranged sufficiently close for coupling radiation from the first deep-shallow waveguide to the second deep-shallow waveguide.

Abstract: An optical coupler for processing radiation is described. The optical coupler comprises a first deep-shallow waveguide and a second deep-shallow waveguide for guiding radiation in a propagation direction. Each of the deep-shallow waveguides is a waveguide comprising a shallow etched portion and an unetched portion having a width substantially constant along the propagation direction. The width of the shallow etched portion is substantially larger than the width of the unetched portion. The shallow etched portion of the first deep-shallow waveguide and the shallow etched portion of the second deep-shallow waveguide are arranged sufficiently close for coupling radiation from the first deep-shallow waveguide to the second deep-shallow waveguide.

Abstract: Disclosed are optical devices for coupling radiation between an optical waveguide and an external medium. In one embodiment, an optical device is disclosed comprising a semiconductor die comprising an integrated optical waveguide core and an overlying optical waveguide comprising a waveguide taper and a waveguide facet. The overlying optical waveguide at least partially overlies the integrated optical waveguide core, and the waveguide facet is between about 1 ?m and 200 ?m from an edge of the semiconductor die. In another embodiment, a method is disclosed comprising providing a substrate comprising an integrated semiconductor waveguide and forming on the substrate an overlying waveguide comprising a waveguide taper and a waveguide facet. The overlying waveguide at least partially overlies the integrated semiconductor waveguide. The method further includes cutting the substrate about 1 ?m and 200 ?m from the waveguide facet.

Abstract: A slanted grating coupler for coupling a radiation beam between a waveguide lying substantially in a plane on a substrate and an optical element outside that plane is provided, whereby the slanted grating coupler has a good coupling efficiency for medium or low index contrast material systems. Furthermore, a method for manufacturing the slanted grating coupler is provided. The slanted grating coupler comprises a plurality of slanted slots extending through the waveguide core and being arranged successively in the propagation direction of the waveguide. In at least part of the coupling region, the size of the slanted slots in a lateral direction, being a direction within the waveguide plane and perpendicular to the propagation direction of the waveguide, is smaller than the lateral size of the waveguide core. Successive slots are displaced with respect to each other in the lateral direction.

Abstract: A slanted grating coupler for coupling a radiation beam between a waveguide lying substantially in a plane on a substrate and an optical element outside that plane is provided, whereby the slanted grating coupler has a good coupling efficiency for medium or low index contrast material systems. Furthermore, a method for manufacturing the slanted grating coupler is provided. The slanted grating coupler comprises a plurality of slanted slots extending through the waveguide core and being arranged successively in the propagation direction of the waveguide. In at least part of the coupling region, the size of the slanted slots in a lateral direction, being a direction within the waveguide plane and perpendicular to the propagation direction of the waveguide, is smaller than the lateral size of the waveguide core. Successive slots are displaced with respect to each other in the lateral direction.

Abstract: An optical waveguide to fiber coupler comprises a substrate, a first waveguide and a second waveguide. The first and second waveguides are formed on the substrate and intersect at a right angle. A diffraction grating structure is formed at the intersection of the first and second waveguides, such that, when the coupler is physically abutted with a single mode optical fiber, in operation, a polarization split is obtained that couples orthogonal modes from the single-mode optical fiber into single identical modes in the first and second waveguides. Also, employing the coupler in optical polarization diverse applications provides for implementing a polarization insensitive photonic integrated circuit using such diffraction grating structures, such as, for example, photonic crystals.

Abstract: An optical waveguide to fiber coupler comprises a substrate, a first waveguide and a second waveguide. The first and second waveguides are formed on the substrate and intersect at a right angle. A diffraction grating structure is formed at the intersection of the first and second waveguides, such that, when the coupler is physically abutted with a single mode optical fiber, in operation, a polarization split is obtained that couples orthogonal modes from the single-mode optical fiber into single identical modes in the first and second waveguides. Also, employing the coupler in optical polarization diverse applications provides for implementing a polarization insensitive photonic integrated circuit using such diffraction grating structures, such as, for example, photonic crystals.