Abstract: A switching network for effecting point-to-point communication between nodes has a time-varying switching configuration, which causes successive activation and deactivation of multiple channels of the switching network, a first of the channels connecting, when activated, a transmitter node and a first receiver node, and a second of the channels connecting, when activated, the transmitter node and a second receiver node.

Abstract: A system for estimating values of a vector of variables that optimize a function comprising a weighted sum of interactions between the variables; the system comprising a plurality of parallel hardware channels, each arranged to model a contribution of a respective variable to the function, each channel comprising: a signal generator configured to generate a signal modelling a value of the respective variable; a splitter arranged to supply the signal to each of the channels; interaction logic configured to multiply the vector of signals by a vector of weights modelling an interaction between the respective variable and the vector of variables, thereby generating a feedback signal representing the contribution of the respective variable; and a feedback path to return the feedback signal to the signal generator configured to adapt the signal in dependence on the feedback signal, wherein each channel is implemented only using optical components and/or analogue electronic components.

Abstract: A system for efficiently interconnecting computing nodes can include a plurality of computing nodes and a plurality of network switches coupled in parallel to the plurality of computing nodes. The system can also include a plurality of node interfaces. Each computing node among the plurality of computing nodes can include at least one node interface for each network switch among the plurality of network switches. The plurality of node interfaces corresponding to a computing node can be configured to send data to another computing node via the plurality of network switches. The system can also include a plurality of switch interfaces. Each network switch among the plurality of network switches can include at least one switch interface for each computing node among the plurality of computing nodes. A switch interface corresponding to the computing node can be coupled to a node interface corresponding to the computing node.

Abstract: A method of fabricating a multi-core polymer optical fibre comprises arranging optical fibre preforms in a stack, the optical fibre preforms each comprising a polymer core and polymer cladding surrounding the polymer core; and drawing and bonding the stack to form the multi-core polymer optical fibre. Any contaminants or impurities which collect on outer surfaces of the preforms may be confined to boundaries between the preforms, which may avoid attenuation of signals passed through the cores while at the same time reducing crosstalk between cores of the final manufactured fibre. Also provided is a multi-core polymer optical fibre obtainable by the method.

Abstract: A switching network for effecting point-to-point communication between nodes has a time-varying switching configuration, which causes successive activation and deactivation of multiple channels of the switching network, a first of the channels connecting, when activated, a transmitter node and a first receiver node, and a second of the channels connecting, when activated, the transmitter node and a second receiver node.

Abstract: An apparatus comprising: a crystal; a wire pair formed of a first wire connected so as to receive a first alternating current, and a second wire connected so as to receive a second alternating current substantially antiparallel to the first alternating current in the first wire, and located adjacent the first wire such that a localized electromagnetic filed is created in a region local to the wire pair via constructive electromagnetic interference between the first wire and the second wire in the region local to the wire pair and destructive electromagnetic field interference between the first wire and the second wire outside of the region local to the wire pair; and a colour centre located within the crystal in the region local to the wire pair.

Abstract: A system for using free-space optics to interconnect a plurality of computing nodes can include a plurality of optical transceivers that facilitate free-space optical communications among the plurality of computing nodes. The system may ensure a line of sight between the plurality of computing nodes and the optical transceivers to facilitate the free-space optical communications. The line of sight may be preserved by the position or placement of the computing nodes in the system. The position or placement of the computing nodes may be achieved by using different shaped enclosures for holding the computing nodes.

Abstract: An apparatus comprising: a crystal; and a colour centre located within the crystal and adapted to receive: a magnetic field, such that a projection of the magnetic field onto a colour centre axis of the colour centre causes a change in an electron spin resonance frequency of the colour centre, and an electromagnetic signal having a frequency that substantially matches the electron spin resonance frequency of the colour centre as changed by the projection of the magnetic field onto the colour centre axis.

Abstract: An apparatus comprising a crystal; at least three first wires arranged substantially parallel to each other; at least two second wires arranged substantially parallel to each other, each second wire arranged non-parallel to each first wire, such that each second wire crosses each first wire, forming at least six cross points; and at least six colour centres, each colour centre located within the crystal adjacent a different one of the at least six cross points.

Abstract: A system for efficiently interconnecting computing nodes can include a plurality of computing nodes and a plurality of network switches coupled in parallel to the plurality of computing nodes. The system can also include a plurality of node interfaces. Each computing node among the plurality of computing nodes can include at least one node interface for each network switch among the plurality of network switches. The plurality of node interfaces corresponding to a computing node can be configured to send data to another computing node via the plurality of network switches. The system can also include a plurality of switch interfaces. Each network switch among the plurality of network switches can include at least one switch interface for each computing node among the plurality of computing nodes. A switch interface corresponding to the computing node can be coupled to a node interface corresponding to the computing node.

Abstract: A system for interconnecting a plurality of computing nodes includes a plurality of optical circuit switches and a plurality of electrical circuit switches. A first network stage comprises a first plurality of circuit switches selected from among the plurality of optical circuit switches and the plurality of electrical circuit switches. Each computing node among the plurality of computing nodes is optically coupled to at least one of the first plurality of circuit switches. A second network stage comprises a second plurality of circuit switches selected from among the plurality of optical circuit switches and the plurality of electrical circuit switches. Each circuit switch among the first plurality of circuit switches is optically coupled to each circuit switch among the second plurality of optical circuit switches.

Abstract: A method of fabricating a graded-index polymer optical fibre comprises preparing a cladding composition, the cladding composition comprising either a mixture of a cladding polymer and a dopant or a mixture of a cladding polymer precursor and a dopant; forming cladding from the cladding composition around a core, the core comprising a core polymer; and causing diffusion of the dopant into the core such that the dopant has a continuous concentration gradient, according to which concentration gradient the concentration of the dopant increases with radial distance from a centre of the core. The dopant is a compound having a refractive index which is lower than a refractive index of the core polymer. By distributing the dopant such that the dopant concentration is lowest at the centre of the core, the optical attenuation of the graded-index polymer optical fibre may be reduced. Also provided is a graded-index polymer optical fibre obtainable by the method.

Abstract: A multi-core optical fibre comprises a plurality of cores embedded in cladding. The cladding comprises a polymer. The cladding has an outer cross-sectional shape with an order of rotational symmetry of less than or equal to 4. By limiting the rotational symmetry of the multi-core optical fibre, rotational alignment of the cores with light sources/light detectors may be made easier. Also provided are optical cables and kits including the multi-core optical fibre, and a method of fabricating a multi-core polymer optical fibre.

Abstract: A method of fabricating a multi-core polymer optical fibre comprises arranging optical fibre preforms in a stack, the optical fibre preforms each comprising a polymer core and polymer cladding surrounding the polymer core; and drawing and bonding the stack to form the multi-core polymer optical fibre. Any contaminants or impurities which collect on outer surfaces of the preforms may be confined to boundaries between the preforms, which may avoid attenuation of signals passed through the cores while at the same time reducing crosstalk between cores of the final manufactured fibre. Also provided is a multi-core polymer optical fibre obtainable by the method.

Abstract: A system for using free-space optics to interconnect a plurality of computing nodes can include a plurality of node optical transceivers that are electrically coupled to at least some of the plurality of computing nodes. The system can also include a plurality of router optical transceivers that facilitate free-space optical communications with the plurality of node optical transceivers. Each node optical transceiver among the plurality of node optical transceivers can have a corresponding router optical transceiver that is optically coupled to the node optical transceiver. The system can also include a router that is coupled to the plurality of router optical transceivers. The router can be configured to route the free-space optical communications among the plurality of computing nodes.

Abstract: A system for interconnecting a plurality of computing nodes includes a plurality of optical circuit switches and a plurality of electrical circuit switches. A first network stage comprises a first plurality of circuit switches selected from among the plurality of optical circuit switches and the plurality of electrical circuit switches. Each computing node among the plurality of computing nodes is optically coupled to at least one of the first plurality of circuit switches. A second network stage comprises a second plurality of circuit switches selected from among the plurality of optical circuit switches and the plurality of electrical circuit switches. Each circuit switch among the first plurality of circuit switches is optically coupled to each circuit switch among the second plurality of optical circuit switches.

Abstract: A system for interconnecting a plurality of computing nodes includes a plurality of optical circuit switches and a plurality of electrical circuit switches. A first network stage comprises a first plurality of circuit switches selected from among the plurality of optical circuit switches and the plurality of electrical circuit switches. Each computing node among the plurality of computing nodes is optically coupled to at least one of the first plurality of circuit switches. A second network stage comprises a second plurality of circuit switches selected from among the plurality of optical circuit switches and the plurality of electrical circuit switches. Each circuit switch among the first plurality of circuit switches is optically coupled to each circuit switch among the second plurality of optical circuit switches.

Abstract: A system for using free-space optics to interconnect a plurality of computing nodes can include a plurality of optical transceivers that facilitate free-space optical communications among the plurality of computing nodes. The system may ensure a line of sight between the plurality of computing nodes and the optical transceivers to facilitate the free-space optical communications. The line of sight may be preserved by the position or placement of the computing nodes in the system. The position or placement of the computing nodes may be achieved by using different shaped enclosures for holding the computing nodes.

Abstract: A switching network for effecting point-to-point communication between nodes has a time-varying switching configuration, which causes successive activation and deactivation of multiple channels of the switching network, a first of the channels connecting, when activated, a transmitter node and a first receiver node, and a second of the channels connecting, when activated, the transmitter node and a second receiver node.

Abstract: A system for using free-space optics to interconnect a plurality of computing nodes can include a plurality of optical transceivers that facilitate free-space optical communications among the plurality of computing nodes. The system may ensure a line of sight between the plurality of computing nodes and the optical transceivers to facilitate the free-space optical communications. The line of sight may be preserved by the position or placement of the computing nodes in the system. The position or placement of the computing nodes may be achieved by using different shaped enclosures for holding the computing nodes.