Abstract: A quantum-dot based avalanche photodiode (QD-APD) may include a silicon substrate and a waveguide on which a quantum dot (QD) stack of layers is formed having a QD light absorption layer, a charge multiplication layer (CML), and spacer layers. The QD stack may be formed within a p-n junction. The waveguide may include a mode converter to facilitate optical coupling and light transfer from the waveguide to the QD light absorption layer. The QD absorption layer and the CML layer may be combined or separate layers. The CML may generate electrical current from the absorbed light with more than 100% quantum efficiency when the p-n junction is reverse-biased.

Abstract: A quantum-dot based avalanche photodiode (QD-APD) may include a silicon substrate and a waveguide on which a quantum dot (QD) stack of layers is formed having a QD light absorption layer, a charge multiplication layer (CML), and spacer layers. The QD stack may be formed within a p-n junction. The waveguide may include a mode converter to facilitate optical coupling and light transfer from the waveguide to the QD light absorption layer. The QD absorption layer and the CML layer may be combined or separate layers. The CML may generate electrical current from the absorbed light with more than 100% quantum efficiency when the p-n junction is reverse-biased.

Abstract: A system for event detection uses a resistive switching device to record a detected event. The resistive switching device has a resistance adjustable by an applied voltage. The operation of the resistive switching device is controlled by a controller, which is configured to apply a switching voltage to the resistive switching device at a start time, and turn off the switching voltage in response to an event signal indicative of occurrence of an event. The resistance value of the resistive switching device resulting from the application of the switching voltage is indicative of the detection of the event and also the time of the occurrence of the event.

Abstract: An optical interconnect has a plurality of optical sources, a first lens configured to collimate optical beams from the plurality of optical sources, a second lens configured to refocus the optical beams, and a plurality of optical receivers configured to receive the refocused optical beams from the second lens.

Abstract: Apparatus and systems are provided for data signaling between a centralized transceiver and a plurality of sensor nodes. Subordinate sensor nodes transmit data corresponding to sensed physical variables to a master node within a group. The master node within the group transmits the data on to a data acquisition transceiver. Data communications are performed by free-space signaling. Large areas can be monitored by a vast array of such sensors, organized as plural neighborhoods, without the need for wiring, optical fibers or other tangible interconnections.

Abstract: An optical apparatus includes a substrate comprising a layer of thermally insulating material disposed thereon; an optical resonator disposed on the layer of thermally insulating material; and a trench in the thermally insulating material disposed around at least a portion of the optical resonator. The optical resonator is substantially thermally isolated from the substrate.

Abstract: A method for forming a photodiode is provided. The method comprises: providing a region of semiconductor material having a first surface and a second surface; coupling a first conductive layer to the first surface of the semiconductor material; and coupling a second conductive surface to the second surface of the semiconductor material to form a photodiode, the second conductive surface comprising a metal surface having a two-dimensional periodic array of openings therethrough, wherein the photodiode is configured to be operated such that light is incident on the second conductive surface. A method for reducing the required thickness of a photodiode is also provided.

Abstract: Examples of a computer system packaged in a three-dimensional stack of dies are described. The package includes an electrical die and an optical die coupled to and stacked with the electrical die. The electrical die includes circuitry to process and communicate electrical signals, and the optical die includes structures to transport optical signals. The electrical die has a smaller area than the optical die so that the optical die includes an exposed mezzanine which is configured with optical input/output ports. Additionally, the packaging can be configured to provide structural support against insertion forces for external optical connections.

Abstract: A system for event detection uses a resistive switching device to record a detected event. The resistive switching device has a resistance adjustable by means of an applied voltage. The operation of the resistive switching device is controlled by a controller, which is configured to apply a switching voltage to the resistive switching device at a start time, and turn off the switching voltage in response to an event signal indicative of occurrence of an event. The resistance value of the resistive switching device resulting from the application of the switching voltage is indicative of the detection of the event and also the time of the occurrence of the event.

Abstract: Various embodiments of the present invention are directed to photonic switches and switch fabrics employing the photonic switches. In one embodiment of the present invention, a photonic switch comprises a first waveguide disposed on a surface of a substrate in proximity to an opening in the substrate, and a second waveguide crossing the first waveguide and positioned in proximity to the opening in the substrate. The photonic switch includes a tunable microring resonator disposed on the surface of the substrate adjacent to the first waveguide and the second waveguide and configured with an opening aligned with the opening in the substrate. The photonic switch also includes a wire having a first end and a second end and configured to pass through the opening in the microring and the opening in the substrate.

Abstract: A method for forming a photodiode is provided. The method comprises: providing a region of semiconductor material having a first surface and a second surface; coupling a first conductive layer to the first surface of the semiconductor material; and coupling a second conductive surface to the second surface of the semiconductor material to form a photodiode, the second conductive surface comprising a metal surface having a two-dimensional periodic array of openings therethrough, wherein the photodiode is configured to be operated such that light is incident on the second conductive surface. A method for reducing the required thickness of a photodiode is also provided.

Abstract: A spatial light modulator includes an array of pixels, with each of the pixels having a dimension smaller than a wavelength of light to be modulated. Each of the pixels further has a permittivity that can he controlled using an electronic signal applied to the pixel.

Abstract: Embodiments of the invention provide a method and an apparatus for forming a photodiode. One embodiment provides a thin dielectric layer sandwiched between two metallic plates (electrodes), one or both of which are periodically patterned in one or two dimensions. The effect of the pattern is to couple incident light within some range of wavelength and/or incidence angles to surface excitations of the metal surface called surface plasmons, enhancing the electric field near the surface and resulting in dramatically increased photo-absorption and carrier generation in the dielectric layer.

Abstract: A method for connecting a photonic crystal fiber having a plurality of cores connected to an optical device. An end of the photonic crystal fiber may be placed on a surface of an optical device having a plurality of coupling pads. A first core of the end of the photonic crystal fiber may be positioned over a first coupling pad on the optical device to enable a threshold amount of a coherent beam of light to propagate through the first core and first coupling pad. A second core of the end of the photonic crystal fiber is aligned to a second coupling pad on the optical device to enable a threshold amount of another coherent beam of light to propagate through the second core and second coupling pad. The end of the photonic crystal fiber may be adhered to the surface of the optical device while the position of the first and the second cores relative to the first and the second coupling pads, respectively, is maintained.

Abstract: Various method and system embodiments of the present invention are directed to executing bit-commitment protocols. In one embodiment of the present invention, a method for executing a bit-commitment protocol for transmitting a bit from a first party to a second party comprises preparing a three qubits are entangled in a W-state, and storing a first of the three qubits in a first storage device controlled by the first party, a second of the three qubits is stored in a second storage device controlled by the second party, and a third of the three qubits is stored in a third storage device controlled by a third party. The bit is revealed to the second party by transmitting the first and third qubits to the second party and measuring the states of the three qubits to which of the entangled W-states the three qubits are in.

Abstract: An optical device includes at least two materials forming a structure with a graded bandgap where photocarriers are generated. A first of the at least two materials has a larger concentration at opposed ends of the graded bandgap structure than a concentration of the first of the at least two materials at an interior region of the graded bandgap structure. The second of the at least two materials has a larger concentration at the interior region of the graded bandgap structure than the concentration of the second of the at least two materials at the opposed ends of the graded bandgap structure.

Abstract: Various embodiments of the present invention are directed to photonic-interconnection-based compute clusters that provide high-speed, high-bandwidth interconnections between compute cluster nodes. In one embodiment of the present invention, the compute cluster includes a photonic interconnection having one or more optical transmission paths for transmitting independent frequency channels within an optical signal to each node in a set of nodes. The compute cluster includes one or more photonic-interconnection-based writers, each writer associated with a particular node, and each writer encoding information generated by the node into one of the independent frequency channels. A switch fabric directs the information encoded in the independent frequency channels to one or more nodes in the compute cluster.

Abstract: A detector includes a light detecting layer and a grating structure. The light detecting layer, which can be a photodiode, has an optical mode that resonates in the light detecting layer, and the grating structure is positioned to interact with the optical mode. The grating structure further couples incident light having a resonant frequency into the optical mode, and causes destructive interference to prevent light having the resonant frequency from escaping the detecting layer. The light detecting layer can be made transparent to light having other frequencies, so that a stack of such detectors, each having a different resonant frequency, can be integrated into a WDM detector that is compact and efficient.

Abstract: A detector includes a light detecting layer and a grating structure. The light detecting layer, which can be a photodiode, has an optical mode that resonates in the light detecting layer, and the grating structure is positioned to interact with the optical mode. The grating structure further couples incident light having a resonant frequency into the optical mode, and causes destructive interference to prevent light having the resonant frequency from escaping the detecting layer. The light detecting layer can be made transparent to light having other frequencies, so that a stack of such detectors, each having a different resonant frequency, can be integrated into a WDM detector that is compact and efficient.

Abstract: An optical device includes at least two materials forming a structure with a graded bandgap where photocarriers are generated. A first of the at least two materials has a larger concentration at opposed ends of the graded bandgap structure than a concentration of the first of the at least two materials at an interior region of the graded bandgap structure. The second of the at least two materials has a larger concentration at the interior region of the graded bandgap structure than the concentration of the second of the at least two materials at the opposed ends of the graded bandgap structure.