California Institute of Technology

Saman Saeedi

Azita Emami

Seyed Ali Hajimiri

Behrooz Abiri

Meisam Honarvar Nazari

Azita Emami-Neyestanak

An optical signal modulator (modulator) includes, in part, a first multitude of diodes coupled in parallel and disposed along an outer periphery of the optical ring of the modulator, a second multitude of diodes coupled in parallel and disposed along the outer periphery of the optical ring, and a doped region adapted to supply heat to the optical ring. A pair of current sources supply substantially constant currents to the first and second multitude of diodes to generate a pair of electrical signals. The modulator further includes, in part, a control circuit adapted to control the temperature of the optical ring in accordance with the pair electrical signals. To achieve this, the control circuit varies the voltage applied to the doped region to vary the supplied heat. Alternatively, the control circuit applies a voltage to the optical ring to maintain a substantially constant resonant wavelength in the optical ring.

Optical ring modulator thermal tuning technique

A differential optical modulator includes, in part, a splitter splitting an incoming optical signal into first and second input signals, a first variable coupler generating a first differential output signal in response to the first input signal, and a second variable coupler generating a second differential output signal in response to the second input signal. The first variable coupler includes, in part, first and second couplers and a phase shifter disposed therebetween. The first coupler generates a pair of internal signals in response to the first input signal. The second coupler generates the first differential output signal. The second variable coupler includes, in part, third and fourth couplers and a phase shifter disposed therebetween. The third coupler generates a pair of internal signals in response to the second input signal. The fourth coupler generates the second differential output signal.

Differential ring modulator

An integrated optical modulator includes, in part, a pair of waveguides and an inductor. The first waveguide is adapted to receive an incoming optical signal. The second waveguide includes a portion placed in proximity of the first waveguide so as to enable the incoming optical signal travelling in the first waveguide to couple to the second waveguide. The second waveguide comprises a p-n junction. The inductor has a first terminal coupled to the p-n junction and a second terminal coupled to a contact pad. The second waveguide has a circular shape. The inductor optionally has a spiral shape.

Bandwidth enhancement technique using inductive peaking

A receiver architecture is disclosed which employs an RC double-sampling front-end and dynamic offset modulation technique. A low-voltage double-sampling technique provides high power efficiency by avoiding linear high-gain elements conventionally employed in typical transimpedance-amplifier (TIA) receivers. In addition, a demultiplexed output of the receiver helps save power in the subsequent digital blocks. Various applications are described including optical receivers, electrical on-chip interconnects, as well as pulse amplitude modulation. The receiver can be implemented in CMOS and is scalable and portable to other technologies.

Growing community of inventors

Pasadena, CA, United States of America

Saman Saeedi