Nexus Photonics LLC

University of California

Facebook Technologies, LLC

Meta Platforms Technologies, LLC

Tin Komljenovic

Minh Tran

Chong Zhang

Hyun Dai Park

Michael Anthony Hall

Qing Chao

Zhaoming Zhu

Zihe Gao

Zeyu Zhang

John E Bowers

Hyundai Park

Roger Jonathon Helkey

Aditya Malik

A device has first, second and third elements fabricated on a common substrate. The first element supports a first optical mode in an active waveguide structure characterized by a mesa. The second element supports a second optical mode in a passive waveguide structure. The third element, at least partly butt-coupled to the first element, supports an intermediate optical mode in an intermediate waveguide structure characterized by a waveguide core cross section including a shallow step. A tapered waveguide structure in at least one of the second and third elements facilitates efficient adiabatic transformation between the second optical mode and the intermediate optical mode. No adiabatic transformation occurs between the intermediate optical mode and the first optical mode. Lithographic alignment marks facilitate precise alignment of the three elements during device fabrication.

Mode control in heterogeneously integrated photonics

A device has first, second and third elements fabricated on a common substrate. The first element supports a first optical mode in a first active waveguide, the second element supports a second optical mode in a second passive waveguide, and the third element, at least partly butt-coupled to the first element, has a bottom waveguide, supporting a bottom intermediate mode, overlying a top waveguide, supporting a top intermediate mode. A tapered waveguide structure in the top waveguide facilitates efficient adiabatic transformation between the top intermediate mode and the bottom intermediate mode. Tapering in at least one of the bottom waveguide and the second waveguide facilitates efficient adiabatic transformation between the second optical mode and the bottom intermediate optical mode. No adiabatic transformation occurs between either of the intermediate optical modes and the first optical mode. Lithographic alignment marks facilitate precise alignment of the three elements during device fabrication.

Heterogenously integrated short wavelength photonic platform with optimally minimal reflections

A device comprises first, second, third and fourth elements fabricated on a common substrate. The first element comprises an active waveguide structure supporting a first optical mode, the second element comprises a passive waveguide structure supporting a second optical mode, the third element, at least partly butt-coupled to the first element, comprises an intermediate waveguide structure supporting intermediate optical modes, and a fourth element comprising TCO material that is attached to the first element. If the first optical mode differs from the second optical mode by more than a predetermined amount, a tapered waveguide structure in at least one of the second and third elements facilitates efficient adiabatic transformation. No adiabatic transformation occurs between any of the intermediate optical modes and the first optical mode. Mutual alignments of the first, the second, the third, and the fourth elements are defined using lithographic alignment marks.

Heterogeneous GaN lasers and active components

A radio frequency generator has first and second lasers configured to emit first and second optical outputs; a reference module configured to receive at least part of the first and second optical outputs from the first and second lasers; a control module connected to the first and second lasers and to the reference module; and an optical-to-electrical (O/E) converter configured to process optical signals, originating from the first and second single-frequency lasers, to provide a radio frequency output. Another radio frequency generator has a control module; and a reference module connected to the control module. The reference module includes a photonic integrated circuit (PIC) having first and second single-frequency lasers configured to emit first and second optical outputs; an unbalanced Mach-Zehnder interferometer (UMZI) with first and second 3×3 optical splitter/combiners; first and second peripheral splitter/combiners; and an output splitter/combiner.

Stabilized frequency generator

A device comprises three elements, realized as photonic integrated circuits. The first element comprises a tunable semiconductor laser emitting light at a laser output wavelength. The second element comprises a wavelength selective element, coupled to the first element. The third element comprises N photodetectors where N>=2, coupled to the second element. Light coupled into the second element from the first element is de-multiplexed by the wavelength selective element such that a ratio of light power coupled from the second element into one of the N photodetectors to light power coupled from the second element into another one of the N photodetectors is a function of the laser output wavelength. The responses of the N photodetectors facilitate at least one of measurement and control of the laser output wavelength.

Wavelength-controlled tunable chip-scale laser

A device has a plurality of waveguide structures including two active (one of which comprises two sub-layers), two passive, and three intermediate waveguide structures on a common substrate. At least partial butt coupling between active and intermediate waveguide structures, and tapering in the intermediate and/or passive waveguide structures at each junction therebetween facilitates efficient optical mode transformations as optical signals travel through the device, either from a first sub-layer of the first active waveguide structure through the other sub-layer, then sequentially though a first intermediate waveguide structure, a passive waveguide structure, a second intermediate waveguide structure, a second active waveguide structure, a third intermediate structure, and a second passive waveguide structure; or in reverse from the second passive waveguide structure back through to the first sub-layer of the first active waveguide structure. Lithographic alignment marks facilitate precise mutual alignments between layers defining each of the waveguide structures.

Active-passive photonic integrated circuit platform

A device comprises first, second and third elements fabricated on a common substrate. The first element comprises an active waveguide structure comprising: a first portion supporting a first optical mode. The second element comprises a passive waveguide structure supporting a second optical mode. The third element, at least partly butt-coupled to the second portion, comprises an intermediate waveguide structure supporting intermediate optical modes. At least part of the second element is non-linear, supporting frequency conversion. A tapered waveguide structure in at least one of the second and third elements facilitates efficient adiabatic transformation between the first optical mode and one intermediate optical mode. No adiabatic transformation occurs between any intermediate optical mode and the first optical mode. Mutual alignments of the elements are defined using lithographic alignment marks.

Heterogeneously integrated photonic platform with non-linear frequency conversion element

A device comprises first, second and third elements fabricated on a common substrate. The first element comprises an active waveguide structure comprising electrically pumped optical source supporting a first optical mode. The second element comprises a passive waveguide structure supporting a second optical mode in at least part of the second element. The third element, at least partly butt-coupled to the first element, comprises an intermediate waveguide structure supporting intermediate optical modes. At least part of the second element supports at least one optical mode that interacts with rare-earth dopants. A tapered waveguide structure in at least one of the second and the third elements facilitates efficient adiabatic transformation between the second optical mode and at least one of the intermediate optical modes. No adiabatic transformation occurs between any of the intermediate optical modes and the first optical mode. Mutual alignments of the elements are defined using lithographic alignment marks.

Heterogeneous photonic integrated circuits with doped waveguides

A device includes three elements fabricated on a common substrate. The first element includes an active waveguide structure having at least three sub-layers supporting a first optical mode. The second element has a passive waveguide structure supporting a second optical mode, and the third element, butt-coupled to the first element, has an intermediate waveguide structure supporting intermediate optical modes. One sub-layer in the active waveguide structure includes an n-contact layer, another sub-layer includes a p-contact layer, and a third sub-layer includes an active region. A tapered waveguide structure in at least one of the second and third elements facilitates efficient adiabatic transformation between the second optical mode and an intermediate optical mode. No adiabatic transformation occurs between that intermediate optical mode and the first optical mode. Mutual alignments of the three elements are defined using lithographic alignment marks that facilitate precise alignment between layers formed fabrication of the elements.

Integrated GaAs active devices with improved optical coupling to dielectric waveguides

A switchable fringe pattern illuminator includes an optical path switch configured to receive light and dynamically control an amount of light that is provided to a first waveguide and an amount of light that is provided to a second waveguide. A first projector configured to generate a first fringe pattern using light from the first waveguide. The first fringe pattern illuminates a first portion of a target area. A second projector configured to generate a second fringe pattern using light from the second waveguide. The second fringe pattern illuminates a second portion of a target area. The illuminator may be part of a depth camera assembly (DCA). The DCA is configured to capture images of a portion of the target area. The DCA is further configured to determine depth information for an object in the target area based in part on the captured images.

Switchable fringe pattern illuminator

A device providing efficient transformation between an initial optical mode and a second optical mode includes first, second and third elements fabricated on a common substrate. The first element includes first and second active sub-layers supporting initial and final optical modes with efficient mode transformation therebetween. The second element includes a passive waveguide structure supporting a second optical mode. The third element, at least partly butt-coupled to the first element, includes an intermediate waveguide structure supporting an intermediate optical mode. If the final optical mode differs from the second optical mode by more than a predetermined amount, a tapered waveguide structure in the second or third elements facilitates efficient transformation between the intermediate optical mode and the second optical mode. Precise alignment of sub-elements formed in one of the elements, relative to sub-elements formed in another one of the elements, is defined using lithographic alignment marks.

A PIC has first, second and third elements fabricated on a common substrate. The first element includes a structure supporting efficient coupling of one or more free-space optical modes of incident light into one or more waveguide guided optical modes. The second element includes an on-chip interferometer having an input optically coupled to the waveguide guided optical modes; one or more arms; one or more outputs; and a phase tuner configured to change optical path length in one or more of the arms. The third element includes one or more light detecting structures optically coupled to the one or more outputs of the second element, such that variation in optical power in the one or more outputs is detected, allowing an assessment of coherence characterizing the light incident on the first element of the PIC to be provided.

Integrated laser detector

A device includes a module comprising an arrayed waveguide grating (AWG), and a filter having a filter input port, a filter output port, and a filter COMM output port. The filter is operable such that a first range of wavelengths entering the filter at the filter input port is directed to the filter output port and a second range of wavelengths entering the filter at the filter input port is directed to the COMM output port. The AWG includes an AWG input port optically coupled to the filter output port to receive the first range of wavelengths, and a plurality of AWG output ports.

Integrated multiplexer with improved performance

An optical device comprises first, second and third elements fabricated on a common substrate. The first element comprises an active waveguide structure supporting a first optical mode, the second element, fabricated on a planarized top surface of the first element, comprises a passive waveguide structure supporting a second optical mode, and the third element, at least partly butt-coupled to the first element, comprises an intermediate waveguide structure, positioned such that a top surface of the intermediate structure underlies a bottom surface of the passive waveguide structure. If the first optical mode differs from the second optical mode by more than a predetermined amount, a tapered waveguide structure in at least one of the second and third elements facilitates efficient adiabatic transformation between the first optical mode and the second optical mode. Mutual alignments of the first, second and third elements are defined using lithographic alignment marks.

Heterogeneously integrated photonic devices with improved optical coupling between waveguides

A device comprises first, second and third elements fabricated on a common substrate. The first element comprises an active waveguide structure comprising: one portion, of effective cross-sectional area A, supporting a first optical mode; and a second portion, butt-coupled to the first portion, of effective cross-sectional area A&#x3e;A. The second element comprises a passive waveguide structure supporting a second optical mode. The third element, at least partly butt-coupled to the second portion, comprises an intermediate waveguide structure supporting intermediate optical modes. If the first optical mode differs from the second optical mode by more than a predetermined amount, a tapered waveguide structure in at least one of the second and third elements facilitates efficient adiabatic transformation between the first optical mode and one intermediate optical mode. No adiabatic transformation occurs between any intermediate optical mode and the first optical mode. Mutual alignments of the elements are defined using lithographic marks.

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Santa Barbara, CA, United States of America

Tin Komljenovic