The disclosure describes various aspects of optical control of atomic quantum bits (qubits) for phase control operations. More specifically, the disclosure describes methods for coherently controlling quantum phases on atomic qubits mediated by optical control fields, applying to quantum logic gates, and generalized interactions between qubits. Various attributes and settings of optical/qubit interactions (e.g., atomic energy structure, laser beam geometry, polarization, spectrum, phase, background magnetic field) are identified for imprinting and storing phase in qubits. The disclosure further describes how these control attributes are best matched in order to control and stabilize qubit interactions and allow extended phase-stable quantum gate sequences.

The disclosure describes various aspects of optical control of atomic quantum bits (qubits) for phase control operations. More specifically, the disclosure describes methods for coherently controlling quantum phases on atomic qubits mediated by optical control fields, applying to quantum logic gates, and generalized interactions between qubits. Various attributes and settings of optical/qubit interactions (e.g., atomic energy structure, laser beam geometry, polarization, spectrum, phase, background magnetic field) are identified for imprinting and storing phase in qubits. The disclosure further describes how these control attributes are best matched in order to control and stabilize qubit interactions and allow extended phase-stable quantum gate sequences.

Accelerating photonic and opto-electronic technologies requires breaking current limits of modern chip-scale photonic devices. While electronics and computer technologies have benefited from “Moore's Law” scaling, photonic technologies are conventionally limited in scale by the wavelength of light. Recent sub-wavelength optical devices use nanostructures and plasmonic devices but still face fundamental performance limitations arising from metal-induced optical losses and resonance-induced narrow optical bandwidths. The present disclosure instead confines and guides light at deeply sub-wavelength dimensions while preserving low-loss and broadband operation. The wave nature of light is used while employing metal-free (all-dielectric) nanostructure geometries which effectively “pinch” light into ultra-small active volumes, for potentially about 100-1000× reduction in energy consumption of active photonic components such as phase-shifters. The present disclosure could make possible all-optical and quantum computing devices which require extreme optical confinement to achieve efficient light-matter interactions.

A method for per-span optical fiber nonlinearity compensation comprises determining values of fiber parameters characterizing one or more target optical fibers in one or more respective spans of a link, and applying selected weight values to one or more photonic computing chips (PCCs), each PCC integrated in a different respective span of the link, wherein selection of the weight values is based on the values of the fiber parameters and a mapping associated with each PCC. The method further comprises transmitting an optical signal through the link, wherein each integrated PCC emulates an inverse of a nonlinear transfer function of the target optical fiber in the respective span, thereby reducing nonlinearity contributed by the one or more target optical fibers to the optical signal.

A method for per-span optical fiber nonlinearity compensation comprises determining values of fiber parameters characterizing one or more target optical fibers in one or more respective spans of a link, and applying selected weight values to one or more photonic computing chips (PCCs), each PCC integrated in a different respective span of the link, wherein selection of the weight values is based on the values of the fiber parameters and a mapping associated with each PCC. The method further comprises transmitting an optical signal through the link, wherein each integrated PCC emulates an inverse of a nonlinear transfer function of the target optical fiber in the respective span, thereby reducing nonlinearity contributed by the one or more target optical fibers to the optical signal.

Systems, devices, apparatuses, components, methods, and techniques for predicting user and media-playback device states are provided. Systems, devices, apparatuses, components, methods, and techniques for media content item caching on a media-playback device are also provided. Systems, devices, apparatuses, components, methods, and techniques for predicting a destination are also provided.

Systems and methods for distributed training of deep learning models are disclosed. An example local device to train deep learning models includes a reference generator to label input data received at the local device to generate training data, a trainer to train a local deep learning model and to transmit the local deep learning model to a server that is to receive a plurality of local deep learning models from a plurality of local devices, the server to determine a set of weights for a global deep learning model, and an updater to update the local deep learning model based on the set of weights received from the server.

The present disclosure relates to an interconnect system for interfacing an electronic subsystem to a qubit package, wherein the qubit package has a plurality of independent qubits. The system makes use of an optical fiber cable having a plurality of optical fibers, which is interfaced to the electronic subsystem. A 3D optical structure is used which has a plurality of internal waveguides, and which is configured to interface the optical fiber cable to the qubit package. The 3D optical structure further has at least one subsystem for using the plurality of waveguides to receive signals of a first type from at least one of the qubits package or the optical fiber cable, to convert the signals from the first type to a second type, and to transmit the signals in the second type to the other one of the fiber optic cable or the qubit package.

The present disclosure relates to an interconnect system for interfacing an electronic subsystem to a qubit package, wherein the qubit package has a plurality of independent qubits. The system makes use of an optical fiber cable having a plurality of optical fibers, which is interfaced to the electronic subsystem. A 3D optical structure is used which has a plurality of internal waveguides, and which is configured to interface the optical fiber cable to the qubit package. The 3D optical structure further has at least one subsystem for using the plurality of waveguides to receive signals of a first type from at least one of the qubits package or the optical fiber cable, to convert the signals from the first type to a second type, and to transmit the signals in the second type to the other one of the fiber optic cable or the qubit package.

A system for scalable, fault-tolerant photonic quantum computing includes multiple optical circuits, multiple photon number resolving detectors (PNRs), a multiplexer, and an integrated circuit (IC). During operation, the optical circuits generate output states via Gaussian Boson sampling (GBS), and the PNRs generate qubit clusters based on the output states. The multiplexer multiplexes the qubit clusters and replaces empty modes with squeezed vacuum states, to generate multiple hybrid resource states. The IC stitches together the hybrid resource states into a higher-dimensional cluster state that includes states for fault-tolerant quantum computation.