Abstract: A holographic data storage system comprises an emitter system, a holographic recording medium, and an input waveguide network formed of one or more multimode optical waveguides. The holographic recording medium has multiple recording regions, each optically coupled to a corresponding one of multiple out-coupling regions of the input waveguide network, the holographic data storage system arranged to persistently write data of an input beam, received at any one of the out-coupling regions, to the corresponding recording region. A controller is coupled to at least one of the emitter system and at least one controllable guiding element of the input waveguide network and controls at least one optical characteristic of the input beam or the at least one guiding element, so as to guide the input beam from an in-coupling region to any selected one of the multiple out-coupling regions. Similar waveguide networks are provided for carrying reference and output beams.

Abstract: A holographic data storage system comprises an emitter system, a holographic recording medium, and an input waveguide network formed of one or more multimode optical waveguides. The holographic recording medium has multiple recording regions, each optically coupled to a corresponding one of multiple out-coupling regions of the input waveguide network, the holographic data storage system arranged to persistently write data of an input beam, received at any one of the out-coupling regions, to the corresponding recording region. A controller is coupled to at least one of the emitter system and at least one controllable guiding element of the input waveguide network and controls at least one optical characteristic of the input beam or the at least one guiding element, so as to guide the input beam from an in-coupling region to any selected one of the multiple out-coupling regions. Similar waveguide networks are provided for carrying reference and output beams.

Abstract: A method of performing a write operation in a holographic data storage system, in which schedule schedules at least one write operation across multiple non-contiguous write intervals, the write operation pertaining to a set of data to be stored in a region of a holographic recording medium. In each of the non-contiguous write intervals, the region of the holographic recording medium is exposed to an interference pattern caused by interference between a reference beam and an input beam carrying the set of data. The multiple non-contiguous write intervals have a total aggregate duration of sufficient length to cause a persistent state change in the exposed region, such that the set of data is recoverable from that region by the end of a final write interval of the multiple non-contiguous write intervals.

Abstract: In an optical data transfer system, a beam modulator is configured to embed a set of data in an input beam. A multimode optical waveguide network has an in-coupling region for receiving the input beam. The multimode optical waveguide network is configured to guide the input beam to an out-coupling region of the multimode optical waveguide network. A spatial coherent detector is configured to measure a phase and an amplitude of an output optical field at multiple locations. The output optical field is at least partially defined by the input beam and thus exhibiting distortion effects caused by the passage of the beam through the multimode waveguide network. Signal processing is applied to an output of the spatial coherent detector, in order to compensate for the distortion effects, and thereby recover, from the output of the spatial coherent detector, the set of data embedded in the input beam.

Abstract: A multimode optical waveguide network comprises a parent waveguide and a plurality of child waveguides. Each waveguide is a multimode optical waveguide having a first surface region, multiple second surface regions, and at least one guiding element attached to a surface of the waveguide or embedded within the waveguide, each second surface region of the parent waveguide optically coupled to the first surface region of a corresponding child waveguide. The guiding element(s) of the parent waveguide is arranged to guide a beam, from or to its first surface region, to or from any selected second surface region of its multiple second surface regions. The guiding element(s) of each of the waveguides is configurable for selecting the second surface region of that waveguide and/or responsive to at least one beam characteristic for selecting the second surface region of that waveguide via modulation of the at least one beam characteristic.

Abstract: Examples are disclosed that relate to encoding data on a data-storage medium. The method comprises obtaining a representation of a measurement performed on the data-storage medium, the representation being based on a previously recorded pattern of data encoded in the data-storage medium in a layout that defines a plurality of data locations. The method further comprises inputting the representation into a data decoder comprising a trained machine-learning function, and obtaining from the data decoder, for each data location of the layout, a plurality of probability values, wherein each probability value is associated with a corresponding data value and represents the probability that the corresponding data value matches the actual data value in the previously recorded pattern of data at a same location in the layout.

Abstract: Examples are disclosed that relate to reading stored data. The method comprises obtaining a representation of a measurement performed on a data-storage medium, the representation being based on a previously recorded pattern of data encoded in the data-storage medium in a layout that defines a plurality of data locations. The method further comprises inputting the representation into a data decoder comprising a trained machine-learning function, and obtaining from the data decoder, for each data location of the layout, a plurality of probability values, wherein each probability value is associated with a corresponding data value and represents the probability that the corresponding data value matches the actual data value in the previously recorded pattern of data at a same location in the layout.

Abstract: In various examples there is a communications network comprising a plurality of nodes connected via an interconnection medium to form a receive-from-many communications network. The network has a synchronisation mechanism which synchronizes a signal frequency of the nodes. The network has at least one store holding signal amplitude data of signals previously sent between specified pairs of nodes of the communications network. An amplitude controller uses the stored data to adjust amplitudes of signals communicated between at least one of the pairs of nodes of the communications network.

Abstract: A wavelength switchable laser is described which has a multi-wavelength laser source configured to generate signals at different wavelengths. The wavelength switchable laser has a wavelength selector with a plurality of electro-optical switches, each electro-optical switch being configurable to transmit or block output of one of the signals from the multi-wavelength source according to the wavelength of the signal.

Abstract: In various examples there is a communications network comprising a plurality of nodes connected via an interconnection medium to form a receive-from-many communications network. The network has a synchronisation mechanism which synchronizes a signal frequency of the nodes. The network has at least one store holding signal amplitude data of signals previously sent between specified pairs of nodes of the communications network. An amplitude controller uses the stored data to adjust amplitudes of signals communicated between at least one of the pairs of nodes of the communications network.

Abstract: A data-storage system comprises a head receiver configured to variably receive up to a number M of write heads. The data-storage system also includes an installed number N of write heads arranged in the head receiver, a substrate receiver configured to receive one or more data-storage substrates, and a positioner machine configured to adjust a relative placement of each of the M write heads with respect to at least one of the one or more data-storage substrates.

Abstract: A data-storage system comprises a head receiver configured to variably receive up to a number M of write heads. The data-storage system also includes an installed number N of write heads arranged in the head receiver, a substrate receiver configured to receive one or more data-storage substrates, and a positioner machine configured to adjust a relative placement of each of the M write heads with respect to at least one of the one or more data-storage substrates.

Abstract: A data-storage system comprises a head receiver configured to variably receive up to a number M of write heads. The data-storage system also includes an installed number N of write heads arranged in the head receiver, a substrate receiver configured to receive one or more data-storage substrates, and a positioner machine configured to adjust a relative placement of each of the M write heads with respect to at least one of the one or more data-storage substrates.

Abstract: A data-storage system comprises a head receiver configured to variably receive up to a number M of write heads. The data-storage system also includes an installed number N of write heads arranged in the head receiver, a substrate receiver configured to receive one or more data-storage substrates, and a positioner machine configured to adjust a relative placement of each of the M write heads with respect to at least one of the one or more data-storage substrates.

Abstract: There is a communications network node comprising a transmitter or a receiver configured to communicate with a plurality of other nodes via an interconnection medium interconnecting the node and the other nodes. The node is frequency synchronized with regard to signal transmission or reception, via a frequency synchronization mechanism, with at least one of the other nodes. The node has at least one store holding phase data relating to an amount of phase asynchrony and path characteristics between the node and at least one of the other nodes. A phase controller uses the stored data to adjust phase used by the node such that the recovery of data when communicating with at least one other node is facilitated.

Abstract: Examples are disclosed that relate to reading stored data. The method comprises obtaining a representation of a measurement performed on a data-storage medium, the representation being based on a previously recorded pattern of data encoded in the data-storage medium in a layout that defines a plurality of data locations. The method further comprises inputting the representation into a data decoder comprising a trained machine-learning function, and obtaining from the data decoder, for each data location of the layout, a plurality of probability values, wherein each probability value is associated with a corresponding data value and represents the probability that the corresponding data value matches the actual data value in the previously recorded pattern of data at a same location in the layout.