USA As Represented by Secretary of the Navy

Marcel W Pruessner

William S Rabinovich

Todd H Stievater

Doewon Park

Rita Mahon

Jacob B Khurgin

Peter G Goetz

Dmitry A Kozak

Brian J Roxworthy

Nathan F Tyndall

An apparatus includes a polarization rotator or a polarization splitter. The polarization rotator and the polarization splitter each includes a first optical waveguide. The polarization rotator further includes a movable symmetry-breaking micro-electro-mechanical systems ('MEMS') dielectric perturber separated from the first optical waveguide by a gap. The first optical waveguide and the MEMS dielectric perturber define a gap therebetween. The polarization rotator also includes a MEMS actuator moving the MEMS dielectric perturber so as to control the gap, thereby controlling polarization rotation within the first optical waveguide. The polarization splitter includes a second optical waveguide separated from the first optical waveguide by a gap. The polarization splitter also includes a MEMS actuator moving the first optical waveguide and/or the second optical waveguide so as to control the gap, thereby controlling polarization splitting between the optical waveguides.

Micromechanically-tunable polarization rotator for photonic integrated circuits

Methods and apparatuses for mode conversion. An apparatus that includes a substrate, a first waveguide, a second waveguide, a micro-electro-mechanical systems (MEMS) perturber, and a controller is provided. The first waveguide is formed on the substrate includes: (i) an input section, (ii) a bend section, and (iii) an output section. The second waveguide is also formed on the substrate and is disposed adjacent to a portion of the input section of the first waveguide. A portion of the second waveguide is separated from the input section of the first waveguide by a coupling gap. The perturber is disposed above the first waveguide and configured to move between a first position that is distal from a surface of the input section of the first waveguide and a second position that is closer to the surface of the input section of the first waveguide than the second position. The controller is configured to control a movement of the perturber between the first position and the second position. When the perturber is in the first position, a mode effective refractive index of the first waveguide is lower than the mode effective refractive index of the first waveguide when the perturber is in the second position.

Methods and apparatuses for optical mode conversion

Optical detectors and methods of forming them are provided. The detector includes: a controller, pump and probe laser generators that generate modulated pump laser and probe lasers, respectively, a microring cavity that receives the lasers, a microbridge, and a photodetector. The microring cavity includes covered and exposed portions. The microbridge is suspended above the exposed portion and interacts with an evanescent optical field. The wavelength and modulated power of the pump laser are controlled to generate the evanescent optical field that excites the microbridge to resonance. The microbridge absorbs optical radiation which changes the resonance frequency proportionately. The probe laser is modulated in proportion to a vibration amplitude of the microbridge to form a modulated probe laser which is provided to the photodetector. The controller receives data from the photodetector, determines a change in resonance frequency, and calculates the amount of absorbed radiation from the change in resonance frequency.

Methods and apparatuses for measuring optical radiation

A device includes a waveguide grating out-coupler, and a tunable uniform phase shifter communicating with the waveguide grating out-coupler. The tunable uniform phase shifter steers a Hat phase front along a first angle in a first plane. Optionally, the waveguide grating out-coupler includes a modulated refractive index and a physical grating period. The tunable uniform phase shifter controls the refractive index, thereby controlling an effective grating period. The grating period relates to die modulated refractive index, and the physical grating period. Optionally, the tunable uniform phase shifter includes a first thermo-optic phase shifter, a first electro-optic phase shifter, or a first micro-electro-mechanical system index perturbation phase shifter. Optionally, the tunable linear gradient phase shifter communicates with the waveguide grating out-coupler and steers a beam along the flat phase front along a second angle in a second plane, which is perpendicular to the first plane.

Chip-scale two-dimensional optical phased array with simplified controls

A device includes an optical splitter comprising a plurality of splitter outputs. The splitter outputs are out of phase and include a non-uniform phase front. The device includes a one-dimensional phase compensation array communicating with the optical splitter. The phase compensation array receives the non-uniform phase front and outputs a uniform phase front. The phase compensation array includes a plurality of array outputs. The device includes a tunable linear gradient phase shifter communicating with said phase compensation array to impart a linearly-varying phase shift across said plurality of array outputs, thereby steering a beam along a first angle in a first plane. The device includes a waveguide grating out-coupler communicating with said linear gradient phase shifter, and a uniform phase shifter communicating with the waveguide grating out-coupler. The uniform phase shifter steers the flat phase front along a second angle in a second plane perpendicular to said first plane.

A method and system described for sensing a displacement by receiving and propagating a laser light signal with an etched waveguide that is configured to enable an evanescent optical field above the waveguide surface. A movable perturber can be positioned so the perturber interacts with the evanescent optical field above the waveguide surface. An optical phase shift can be induced in the waveguide when the movable perturber is displaced in the evanescent optical field, and the optical phase shift can be measured with an optical readout circuit.

Evanescent field opto-mechanical displacement sensor

Evanescent field opto-mechanical phase shifter

A mass sensor system including multiple Fabry-Perot microcavities connected in parallel by multiple waveguides. Each of the mass sensors includes a microbridge having a fundamental resonance frequency, and a movable reflective mirror etched into the microbridge; a fixed reflective mirror etched in a substrate, the fixed reflective mirror being fixed to the substrate in a region spaced apart from the movable reflective mirror; and an optical waveguide etched in the substrate that connects the movable mirror and the fixed mirror forming the Fabry-Perot microcavity interferometer. The system includes a tunable continuous-wave laser operative to optically interrogate the Fabry-Perot microcavity of each of the plurality of mass sensors, and a receiver operative to receive sensor signals from each of the plurality of mass sensors, the sensor signals comprising reflective signals and transmitted signals. A continuous-wave laser may generate optical forces that modify the motion, dynamics, or mechanical Q-factor of the microbridge.

Cavity opto-mechanical sensor system

A waveguide device for frequency mixing or conversion through birefringent phase matching, having a horizontal waveguide suspended above a substrate. The waveguide is formed of a zinc blend type III-V semiconductor material with a high nonlinear susceptibility.

Nonlinear frequency conversion in nanoslab optical waveguides

Cavity opto-mechanical sensor array

A change in mass of a microbridge in a mass sensor can be sensed by applying a time-varying amplitude modulated electrostatic force to excite the microbridge into resonance at the frequency of amplitude modulation. An optical energy is then transmitted at a wavelength close to a resonant wavelength of a Fabry-Perot microcavity, which is formed by etching a movable reflective mirror into a region of the microbridge and by etching a fixed reflective minor in a region spaced apart from the microbridge. The two mirrors are interconnected by an optical waveguide. The movable mirror and fixed mirror reflect the optical energy to a receiver, and a change in the Fabry-Perot microcavity's reflectivity is interferometrically determined. The change in reflectivity indicates a change in the microbridge's resonant frequency due to increased mass of the microbridge resulting from sorption of a target chemical by a layer of chemoselective material deposited on the microbridge.

Optical MEMS chemical sensor array

A waveguide device for frequency mixing or conversion through birefringent phase matching, having two suspended horizontal waveguides with an air-filled horizontal nanoslot between them. The waveguides are formed of a material with a high nonlinear susceptibility, and one waveguide can be n-doped with the other waveguide slab being p-doped. The system can be tuned to operate at different frequencies by varying the nanoslot gap distance by electrostatically actuating the suspended air-clad waveguides.

Growing community of inventors

Silver Spring, MD, United States of America

Marcel W Pruessner