An electrical-optical modulator may include a first section configured for a first electrical-optical interaction between one or more optical waveguides and one or more signal electrodes. The electrical-optical modulator may include a second section configured to increase or decrease a relative velocity of signals of the one or more signal electrodes to optical signals of the one or more optical waveguides relative to the first section. The electrical-optical modulator may include a third section configured for a second electrical-optical interaction between the one or more optical waveguides and the one or more signal electrodes according to an opposite modulation polarity relative to the first section.

An electro-optic modulator comprises a resonator comprising a first waveguide having a first end and second end; a first grating at the first end; and a second grating at the second end. An input channel is in communication with the resonator, and comprises a second waveguide having a first end and second end; an input port at the first end; a third grating at the second end; and a first coupler configured to couple light between the second waveguide and the first waveguide. An output channel is in communication with the resonator, and comprises a third waveguide having a first end and second end; an all-pass filter at the first end; a readout port at the second end; and a second coupler configured to couple light between the first and third waveguides. The all-pass filter is configured to adjust a coupling strength between the second coupler and the readout port.

Structures for an optical power modulator and methods of fabricating a structure for an optical power modulator. A first waveguide core includes first and second sections. A second waveguide core includes a first section laterally adjacent to the first section of the first waveguide core and a second section laterally adjacent to the second section of the first waveguide core. An interconnect structure is formed over the first waveguide core and the second waveguide core. The interconnect structure includes first and second transmission lines. The first transmission line is physically connected within the interconnect structure to the first section of the first waveguide core. The second transmission line includes a first section physically connected within the interconnect structure to the second section of the first waveguide core and a second section adjacent to the first transmission line.

Techniques for termination for microring modulators are disclosed. In the illustrative embodiment, a microring modulator on a photonic integrated circuit (PIC) die is modulated by radiofrequency (RF) signals connected to electrodes across the microring modulator. A resistor is connected to each of the electrodes. The resistors both provide termination for the RF signals, preventing or reducing reflections, as well as forming part of a bias tee, allowing for a DC bias voltage to be applied across the electrodes.

A carrier depletion-based Silicon Photonic (SiP) modulator using capacitive coupling includes a high-k dielectric material in or on slabs, between a rib. A capacitance (C.sub.k) of the high-k dielectric material is larger than a capacitance (C.sub.pn) of the rib, thereby reducing the high frequency impedance and improving bandwidth of the modulator. A modulator includes a first electrode; a first slab connected to the first electrode at a first end; a rib connected to the first slab at a second end of the first slab; a second slab connected to the rib at a first end; a second electrode connected to the second slab at a second end of the second slab; and a high-k dielectric material disposed in or on a portion of each of the first slab and the second slab, thereby enabling capacitive coupling.

This application relates to circuits and methods for dynamically correcting DC bias and suppressing optical carrier frequency in electro-optic modulators (EOMs). A DC bias voltage for a control path may be determined using a control path DC bias structure. DC bias in a signal path may be corrected by applying the DC bias voltage, or a function thereof, to a signal path DC bias structure. Signal path and control path RF signal structures may be operated for a time period during which their DC biases drift together. An updated DC bias voltage for the control path may be determined using the control path DC bias structure. The drift of DC bias in the signal path may be corrected by applying the updated DC bias voltage, or a function thereof, to the signal path DC bias structure.

This application relates to circuits and methods for dynamically correcting DC bias and suppressing optical carrier frequency in electro-optic modulators (EOMs). A DC bias voltage for a control path may be determined using a control path DC bias structure. DC bias in a signal path may be corrected by applying the DC bias voltage, or a function thereof, to a signal path DC bias structure. Signal path and control path RF signal structures may be operated for a time period during which their DC biases drift together. An updated DC bias voltage for the control path may be determined using the control path DC bias structure. The drift of DC bias in the signal path may be corrected by applying the updated DC bias voltage, or a function thereof, to the signal path DC bias structure.

An optical device includes a substrate W, a RF modulating unit, and a phase adjustment unit 220. The RF modulating unit is provided on the substrate W and modulates light in accordance with a RF signal. The phase adjustment unit 220 is provided on the substrate W and adjusts the phase of an optical signal modulated by the RF modulating unit. The phase adjustment unit 220 includes a heater 2200 and a to-be-heated optical waveguide 2201. The to-be-heated optical waveguide 2201 is provided between a thin film LN substrate 32 and a buffer layer 33 of the substrate W, and is formed of a material having a thermo-optical effect. The heater 2200 is provided at a position opposite the to-be-heated optical waveguide 2201, with the buffer layer 33 therebetween on the substrate W, and heats the to-be-heated optical waveguide 2201.

An electro-optic modulator includes a base plate, an optical waveguide, at least one set of modulation electrodes, and an electromagnetic shielding structure. The electromagnetic shielding structure includes a top shielding member covering the set of modulation electrodes from above, and a side shielding member disposed on two sides of the set of modulation electrodes. At least a portion of the side shielding member extends into the base plate to isolate the set of modulation electrodes.

An optical modulator includes: a Mach-Zehnder modulator; and a processor that controls a bias of the Mach-Zehnder modulator. The Mach-Zehnder modulator includes first and second Mach-Zehnder interferometers that are respectively formed on first and second optical paths, a phase shifter that adjusts a phase difference between the first optical path and the second optical path. The processor outputs a first bias signal for controlling an operation point of the first Mach-Zehnder interferometer, a second bias signal for controlling an operation point of the second Mach-Zehnder interferometer, and a third bias signal for controlling a phase-shift amount of the phase shifter, a low-frequency signal being superimposed on the third bias signal. The processor controls the first through third bias signals based on a frequency component of the low-frequency signal that is included in the optical signal output from the Mach-Zehnder modulator.