University of California

Other

Arthur Charles Gossard

John E Bowers

Justin Norman

Andrew William Jackson

Daehwan Jung

Jan Arild Tofte

Paul Ruengrit Pinsukanjana

Scott A Chalmers

Chen Shang

Yating Wan

John H English

Paul K Hansma

Ali Shakouri

Kunal Mukherjee

Jennifer Selvidge

Alan Young Liu

Albrecht L Weisenhorn

Joshua M O Zide

A quantum dot (QD) laser comprises a semiconductor substrate and an active region epitaxially deposited on the semi-conductor substrate. The active region includes a plurality of barrier layers and a plurality of QD layers interposed between each of the plurality of barrier layers. A net compressive strain associated with the plurality of QD layers is maintained below a maximum allowable strain to prevent formation of misfit dislocations within the active region of the QD laser.

Quantum dot lasers and methods for making the same

A photonic integrated circuit (PIC) includes a semiconductor substrate, one or more passive components, and one or more active components. The one or more passive components are fabricated on the semiconductor substrate, wherein the passive components are fabricated in a III-V type semiconductor layer. The one or more active components are fabricated on top of the one or more passive components, wherein optical signals are communicated between the one or more active components via the one or more passive components.

Monolithic integrated quantum dot photonic integrated circuits

A silicon-photonic integrated circuit comprising a direct-bandgap-semiconductor-based active optical device that is epitaxially grown on an indirect-bandgap SOI substrate () is disclosed. The structure of the active optical device includes an active region () having quantum dots () made of InGaAs that are embedded in one or more confinement layers (n-InP, p-InP), where the bandgap of the confinement layers is higher than that of the quantum dots. Further the confinement-layer material is preferably lattice matched to the quantum dot material in order to suppress associated crystalline defects within the material are located away from the center of its bandgap such that they suppress recombination-enhanced defect-reaction-driven degradation of the active optical device. The active optical device is epitaxially grown on a handle substrate of an SOI substrate that has a surface waveguide formed in its device layer, where the active region and the surface waveguide are at the same height above the handle wafer surface.

Integration of direct-bandgap optically active devices on indirect-bandgap-based substrates

Composite epitaxial materials that comprise semimetallic ErAs nanoparticles or nanoislands epitaxially embedded in a semiconducting InGaAs matrix both as superlattices and randomly distributed throughout the matrix are disclosed. The presence of these particles increases the free electron concentration in the material while providing scattering centers for phonons. Electron concentration, mobility, and Seebeck coefficient of these materials are discussed and their potential for use in thermoelectric power generators is postulated. These composite materials in accordance with the present invention have high electrical conductivity, low thermal conductivity, and a high Seebeck coefficient. The ErAs nanoislands provides additional scattering mechanism for the mid to long wavelength phonon&#x2014;the combination reduces the thermal conductivity below the alloy limit.

High efficiency thermoelectric materials based on metal/semiconductor nanocomposites

An integrated dual beam multi-channel optical-based flux monitor and method of monitoring atomic absorption of a plurality of atomic species during epitaxial growth. Light from multiple sources is simultaneously passed through a region of deposition of material such that atomic absorption takes place. The light that passed through the region is then compared to light in a reference arm that did not pass through a region of atomic absorption. From this comparison the growth of an epitaxial layer can be carefully controlled.

Integrated multi-channel optical-based flux monitor and method

An integrated dual beam multi-channel optical-based flux monitor and method of monitoring atomic absorption of a plurality of atomic species during epitaxial deposition. Light from multiple sources is simultaneously passed through a region of deposition of material such that atomic absorption takes place. The light that passed through the region is then compared to light in a reference arm that did not pass through a region of atomic absorption. From this comparison the deposition of an epitaxial layer can be carefully monitored and controlled.

Method of controlling multi-species epitaxial deposition

An ultragrating is a nanometer-period optical grating that is fabricated from a horizontal superlattice. A superlattice is a material structure grown on a substrate by molecular-beam epitaxy or metal-organic chemical vapor deposition and having periodic compositional variations. A horizontal superlattice is one in which the compositional variations are in a direction parallel to the substrate surface. By the selective removal of one of the superlattice materials, an ultragrating is obtained. The smallest grating periods possible before this discovery were those made by electron-beam lithographic techniques which are limited to values greater than 100 nanometers. Thus, the ultragrating with grating periods ranging from one to a hundred nanometers represents an order of magnitude advancement in the state of the art of making optical gratings. The ultragrating will fine utility in the design of advanced electronic devices and for general scientific and engineering purposes.

Growing community of inventors

Santa Barbara, CA, United States of America

Arthur Charles Gossard