Provided is an optical phase shifter. The optical phase shifter includes: a slab waveguide in which a first slab region doped into a first conductivity type and a second slab region doped into a second conductivity type are arranged side by side to form a PN junction; and a rib waveguide disposed on the slab waveguide such that one side of the rib waveguide makes contact with the first slab region, and an opposite side of the rib waveguide makes contact with the second slab region, wherein the rib waveguide includes first to third rib waveguide layers that are sequentially stacked, the first and third rib waveguide layers include silicon (Si), and the second rib waveguide layer includes silicon-germanium (SiGe).

Provided is an optical phase shifter. The optical phase shifter includes: a slab waveguide in which a first slab region doped into a first conductivity type and a second slab region doped into a second conductivity type are arranged side by side to form a PN junction; and a rib waveguide disposed on the slab waveguide such that one side of the rib waveguide makes contact with the first slab region, and an opposite side of the rib waveguide makes contact with the second slab region, wherein the rib waveguide includes first to third rib waveguide layers that are sequentially stacked, the first and third rib waveguide layers include silicon (Si), and the second rib waveguide layer includes silicon-germanium (SiGe).

Structures including an electro-optical phase shifter and methods of fabricating a structure including an electro-optical phase shifter. The structure includes a waveguide core on a semiconductor substrate, and an interconnect structure over the waveguide core and the semiconductor substrate. The waveguide core includes a phase shifter, and the interconnect structure includes a slotted shield and a transmission line coupled to the phase shifter. The slotted shield includes segments that are separated by slots. The slotted shield is positioned between the transmission line and the substrate.

The invention refers to an optical device for heterodyne interferometry, comprising a chip, a beam splitter, a first waveguide arranged on the chip, light propagating in the first waveguide being guided to the beam splitter, a second waveguide arranged on the chip, light propagating in the second waveguide being guided to and/or from the beam splitter, wherein the beam splitter, the first waveguide, and the second waveguide form part of a Michelson interferometer, wherein the first waveguide and the second waveguide at least partially form two arms of the Michelson interferometer, and wherein two further arms of the Michelson interferometer are at least partially arranged outside the chip.

A photonic integrated circuit (PIC) device has photonic devices arranged in an array with respect to control and common conductors. Each of the photonic devices has a photonic component (e.g., photodiode, thermo-optic phase shifter, etc.) and a switching diode connected in series with one another between a control connection and a common connection. The photonic component has at least one optical port, which can be coupled to a waveguide in the PIC device. The switching diode is configured to switch between reverse and forward bias in response to the electrical signals. In this way, control circuitry for providing control and monitoring signals to the conductors can be greatly simplified, and the PIC device can be more compact.

A device, such as an electroabsorption modulator, can modulate a light intensity by controllably absorbing a selectable fraction of the light. The device can include a substrate. A waveguide positioned on the substrate can guide light. An active region positioned on the waveguide can receive guided light from the waveguide, absorb a fraction of the received light, and return a complementary fraction of the received light to the waveguide. Such absorption produces heat, mostly at an input portion of the active region. The input portion of the active region can be thermally coupled to the substrate, which can dissipate heat from the input portion, and can help avoid thermal runaway of the device. The active region can be thermally isolated from the substrate away from the input portion, which can maintain a relatively low thermal mass for the active region, and can increase efficiency when heating the active region.

A device, such as an electroabsorption modulator, can modulate a light intensity by controllably absorbing a selectable fraction of the light. The device can include a substrate. A waveguide positioned on the substrate can guide light. An active region positioned on the waveguide can receive guided light from the waveguide, absorb a fraction of the received light, and return a complementary fraction of the received light to the waveguide. Such absorption produces heat, mostly at an input portion of the active region. The input portion of the active region can be thermally coupled to the substrate, which can dissipate heat from the input portion, and can help avoid thermal runaway of the device. The active region can be thermally isolated from the substrate away from the input portion, which can maintain a relatively low thermal mass for the active region, and can increase efficiency when heating the active region.

Provided is an electro-absorption modulator that includes a substrate, a mesa structure, a first conductivity type electrode, and a second conductivity type electrode. The first conductivity type electrode includes a mesa-top electrode, a pad electrode, and a lead-out wire electrode. The mesa structure has a light input end, to which light is to be input from outside, and a light output end, which is on a side of the mesa structure that is opposite of the light input end. A connection position between a center position in a short-side direction of the lead-out wire electrode and the mesa-top electrode is closer to the light output end side in a long-side direction of the mesa-top electrode. The connection position is a position that is less than 50% from the light output end side with respect to a length in the long-side direction of the mesa-top electrode.

Provided is an electro-absorption modulator that includes a substrate, a mesa structure, a first conductivity type electrode, and a second conductivity type electrode. The first conductivity type electrode includes a mesa-top electrode, a pad electrode, and a lead-out wire electrode. The mesa structure has a light input end, to which light is to be input from outside, and a light output end, which is on a side of the mesa structure that is opposite of the light input end. A connection position between a center position in a short-side direction of the lead-out wire electrode and the mesa-top electrode is closer to the light output end side in a long-side direction of the mesa-top electrode. The connection position is a position that is less than 50% from the light output end side with respect to a length in the long-side direction of the mesa-top electrode.

An optoelectronic device. The optoelectronic device comprising: a rib waveguide provided on a substrate of the device, the rib waveguide comprising a ridge portion and a slab portion; a heater, disposed within the slab portion; a thermally isolating trench, adjacent to the rib waveguide, and extending into the substrate of the device; and a thermally isolating cavity within the substrate, which is directly connected to the thermally isolating trench, and which extends across at least a part of a width of the rib waveguide between the rib waveguide and the substrate.