Patent classifications
G02F1/0353
Optical modulator RF electrodes
The performance of an electro-optic modulator depends in part on the capacitance, the inductance, the electric field distribution, and the signal insertion loss of a microwave transmission line that modulates the refractive index of a waveguide via the electro-optic effect. Conventional electro-optic modulators are typically unable to improve one of these properties without negatively affecting other properties, resulting in lower performance. These shortcomings may be overcome, in part, by the inclusion of capacitive structures to decouple these properties. The capacitive structure may include a fang and/or a hook to tune the capacitance and the electric field distribution without appreciably changing the inductance or the signal insertion losses. The inductance and the signal insertion losses may be tuned by changing the sizes and shapes of a signal conductor, a ground conductor, and a slot formed between the signal and ground conductors without appreciably changing the capacitance or the electric field distribution.
SAW Modulators and Light Steering Methods
An electro-holographic light field generator device is disclosed. The light field generator device has an optical substrate with a waveguide face and an exit face. One or more surface acoustic wave (SAW) optical modulator devices are included within each light field generator device. The SAW devices each include a light input, a waveguide, and a SAW transducer, all configured for guided mode confinement of input light within the waveguide. A leaky mode deflection of a portion of the waveguided light, or diffractive light, impinges upon the exit face. Multiple output optics at the exit face are configured for developing from each of the output optics a radiated exit light from the diffracted light for at least one of the waveguides. An RF controller is configured to control the SAW devices to develop the radiated exit light as a three-dimensional output light field with horizontal parallax and compatible with observer vertical motion.
Ultra-responsive phase shifters for depletion mode silicon modulators
A novel phase shifter design for carrier depletion based silicon modulators, based on an experimentally validated model, is described. It is believed that the heretofore neglected effect of incomplete ionization will have a significant impact on ultra-responsive phase shifters. A low VL product of 0.3 V.Math.cm associated with a low propagation loss of 20 dB/cm is expected to be observed. The phase shifter is based on overlapping implantation steps, where the doses and energies are carefully chosen to utilize counter-doping to produce an S-shaped junction. This junction has a particularly attractive VL figure of merit, while simultaneously achieving attractively low capacitance and optical loss. This improvement will enable significantly smaller Mach-Zehnder modulators to be constructed that nonetheless would have low drive voltages, with substantial decreases in insertion loss. The described fabrication process is of minimal complexity; in particular, no high-resolution lithographic step is required.
SAW modulators and light steering methods
An electro-holographic light field generator device is disclosed. The light field generator device has an optical substrate with a waveguide face and an exit face. One or more surface acoustic wave (SAW) optical modulator devices are included within each light field generator device. The SAW devices each include a light input, a waveguide, and a SAW transducer, all configured for guided mode confinement of input light within the waveguide. A leaky mode deflection of a portion of the waveguided light, or diffractive light, impinges upon the exit face. Multiple output optics at the exit face are configured for developing from each of the output optics a radiated exit light from the diffracted light for at least one of the waveguides. An RF controller is configured to control the SAW devices to develop the radiated exit light as a three-dimensional output light field with horizontal parallax and compatible with observer vertical motion.
A PHOTONIC DEVICE
A single-photon light source (2) comprises a photonic crystal structure the lattice of which extends in at least two dimensions and includes a crystal defect defining an optical waveguide (13) for guiding optical radiation emitted within the photonic crystal. An electric field generator (3) is operable to apply an electric field to the photonic crystal. A light emitter selected from: a quantum dot; a quantum well; a light-emitting diode (LED), is arranged within the photonic crystal for responding to the electric field to acquire an excited state and by decaying from the excited state thereby emitting optical radiation into the photonic crystal for guiding by the optical waveguide. The single-photon light source may be used as part of a quantum key distribution transmitter. An integrated single-photon detector (64) is disclosed as part of a quantum key distribution receiver.
Optical modulator using the spin hall effect in metals
The spin-Hall effect can be used to modulate the linear polarization of light via the magneto-optical Kerr effect. A central area of an outer surface of an added layer atop a spin Hall material is illuminated while simultaneously passing a modulated electric current through the material, so that reflected light has a new linear polarization that differs from the initial linear polarization to a degree depending on the amplitude of the modulated electric current.
POLARIZATION CONTROL WITH LOW POLARIZATION-MODE DISPERSION
Optical polarization control devices that include two pairs of squeezing plates oriented in mutually perpendicular directions are described. Compressive forces exerted by the two pairs of plates onto an optical fiber can be configured for low polarization mode dispersion. Various methods and systems in which the polarization control devices can be employed are also described.
Optical device and optical communication apparatus
An optical device includes a plurality of first Si waveguides that split and output an optical signal received from an input unit, plurality of LN waveguides that are included in a LN modulator and that transmit the optical signals that are split and output by the first Si waveguides, and a plurality of second Si waveguides that multiplex and output the associated optical signals that are output from the plurality of respective LN waveguides. The device includes an output unit that outputs the optical signal multiplexed by the second Si waveguides, and a plurality of Mach-Zehnder interferometers disposed on each of waveguides connected by the first Si waveguides, the LN waveguides, and the second Si waveguides, respectively. When there are differences among waveguide lengths of the LN waveguides, the device is configured such that the optical path lengths of the waveguides for the respective Mach-Zehnder interferometers are equalized.
Data center
A data center includes a wavelength source, a first optical component, a first communications device, and a second communications device. The wavelength source is configured to generate an N-wavelength laser beam. The first port of the first optical component is configured to receive an M-wavelength laser beam from the wavelength source. The second port of the first optical component is configured to send the M-wavelength laser beam to the first communications device. The M-wavelength laser beam includes at least a first-wavelength laser beam. The second port of the first optical component is further configured to receive a modulated first optical signal from the first communications device, the modulated first optical signal is obtained after the first communications device modulates a service signal onto the first-wavelength laser beam. The third port of the first optical component is configured to send the modulated first optical signal to the second communications device.
Light field generator devices with series output couplers
Electro-holographic light field generator devices comprising surface acoustic wave (SAW) optical modulators are disclosed that employ multiple output couplers. These output couplers might be distributed along waveguides of the SAW modulators, within output coupling regions. Each of these output couplers can be configured for directing an incident leaky mode light at different output angles. In some cases, it may be desirable to employ the output couplers to function as different sub-pixels, to provide light to different viewing directions. The output couplers may be mirrors, volume gratings, chirped gratings, reflection gratings, two dimensional gratings, and/or transmission gratings. The output couplers may be angled so that the coupling output fans for each optical modulator are offset from the waveguide for that optical modulator.