摘要:
An avalanche photodiode with a defect-assisted silicon absorption region. An example includes a substrate; a layer of silicon on the substrate, the layer of silicon including a positively-doped region, a negatively-doped region, and an absorption region between the positively-doped and negatively-doped regions, the absorption region including defects in its crystal structure; and contacts in electrical communication with the positively-doped and negatively-doped regions to receive a bias potential.
摘要:
In one example, a composite processor includes a circuit board, a first processor element package, and a second processor element package. The circuit board has an optical link and an electrical link. The first processor element package includes a substrate with an integrated circuit, a sub-wavelength grating optical coupler, and an electrical coupler coupled to the electrical link of the circuit board. The second processor element package includes a substrate with an integrated circuit, a sub-wavelength grating optical coupler, and an electrical coupler coupled to the electrical link of the circuit board. The sub-wavelength grating optical coupler of the first processor element package, the optical link of the circuit board, and the sub-wavelength grating optical coupler of the second processor element package collectively define an optical communications path between the substrate of the first processor element package and the substrate of the second processor element package.
摘要:
A process for entangling quantum states of respective quantum systems measures electromagnetic radiation emitted from a first system and from a second system. The two systems are exposed to excitation radiation having a probability per time of producing a photon, and an interference element is coupled to receive photons from the first and second systems. The process further includes measuring a time during which the first and second systems were exposed to the excitation radiation before a photon is detected on either output channel of the interference element and applying an electromagnetic pulse that causes a relative phase shift of a portion of a quantum state of the first and second systems. Parameters of the electromagnetic pulse are selected based on measurements of the electromagnetic radiation from the first and second systems and the time measured.
摘要:
A micro-ring resonator includes a bus optical waveguide and a circular optical waveguide positioned adjacent to the bus optical waveguide so as to provide evanescent coupling of light between the waveguides. The cladding of the circular optical waveguide comprises an electro-optic polymer with an index of refraction that can be changed through application of an electric field.
摘要:
A resonant cavity, including a gain medium and a color center formed in the gain medium, is to be used for lasing in a system. The color center includes a lower laser level based on a plurality of spin states that are affected by a magnetic field. A gain associated with the system depends on the plurality of spin states. The system is to produce light based on lasing by the resonant cavity in response to application of pump energy to pump the color center. An intensity of the produced light is affected by the magnetic field in the presence of microwaves.
摘要:
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 be controlled using an electronic signal applied to the pixel.
摘要:
A vertical cavity surface emitting laser (VCSEL) system and method of fabrication are included. The VCSEL system includes a gain region to amplify an optical signal in response to a data signal and a first mirror arranged as a partially-reflective high-contrast grating (HCG) mirror at an optical output of the VCSEL system. The VCSEL system also includes a second mirror. The first and second mirrors can be arranged as a laser cavity to resonate the optical signal. The VCSEL system further includes a doped semiconductor region to generate a current through the first mirror in response to a voltage signal to substantially alter the reflectivity of the first mirror to provide Q-switching capability of the VCSEL system.
摘要:
Light-detection systems that do not destroy the light to be detected or change the propagation direction of the light are described. In one aspect, a light-detection system includes an optical element composed of a substrate with a planar surface and a polarization insensitive, high contrast, sub-wavelength grating composed of posts that extend from the planar surface. The posts and/or lattice arrangement of the posts are non-periodically varied to impart orbital angular momentum and at least one helical wavefront on the light transmitted through the optical element.
摘要:
An apparatus for performing surface enhanced Raman spectroscopy includes an optical waveguide, a plurality of flexible nano-structures, wherein the plurality of nano-structures have respective free ends positioned within an evanescent field to be generated by light propagated through the optical waveguide, wherein the plurality of nano-structures are movable from a first position and a second position, wherein in the first position, the free ends of the plurality of nano-structures are substantially spaced from each other and in the second position, the free ends of a plurality of the nano-structures are substantially in contact with each other.
摘要:
A method and system for compensating for motion blur in optical navigation adds a correction offset to an image navigation value to adjust for varying velocities along a moving web. Reference and comparison images are acquired at different times from a moving web. An optical navigation value is computed representative of the movement of the web from the reference image to the comparison image. Blur distances for the two images can be calculated. A navigation error correction value is computed as one-half the difference between the reference blur distance and the comparison blur distance. A compensated navigation value is computed by adding the error correction value to the computed navigation value to compensate for varying web velocities.