December 10, 2018

''Spectrally pure lasers, the heart of precision high-end scientific and commercial applications, are poised to make the leap from the laboratory to integrated circuits. Translating this performance to integrated photonics will dramatically reduce cost and footprint for applications such as ultrahigh capacity fibre and data centre networks, atomic clocks and sensing. Despite the numerous applications, integrated lasers currently suffer from large linewidth. Brillouin lasers, with their unique properties, offer an intriguing solution, yet bringing their performance to integrated platforms has remained elusive. Here, we demonstrate a sub-hertz (~0.7 Hz) fundamental linewidth Brillouin laser in an integrated Si3N4 waveguide platform that translates advantages of non-integrated designs to the chip scale. This silicon-foundry-compatible design supports low loss from 405 to 2,350 nm and can be integrated with other components. Single- and multiple-frequency output operation provides a versatile low phase-noise solution. We highlight this by demonstrating an optical gyroscope and a low-phase-noise photonic oscillator.''

Full-text version of our Nature Photonics publication can be found via the Springer Nature SharedIt link here



November 15, 2018

Energy efficiency project, funded by DOE ARPA-E OPEN 2018 Program award for FRESCO: Frequency Stabilized Coherent Optical Low-energy Wavelength Division Multiplexing, PI: Daniel J. Blumenthal (OCPI)


ARPA-E’s OPEN 2018 Program Selects Innovative Technologies to Advance Energy Security and Competitiveness

University of California-Santa Barbara – Santa Barbara, CA
FRESCO: Frequency Stabilized Coherent Optical Low-energy Wavelength Division Multiplexing (WDM) DC Interconnects – $3,750,000
"The University of California-Santa Barbara will develop a low power, low-cost solution to overcome power and bandwidth scaling limitations presented by the emergence of hyperscale data centers and related exponential growth in global data traffic. The FRESCO transceiver leverages recent advances in fundamental laser physics to enable terabit, coherent optical (light-based) data transmission inside data centers using an ultra-pure and ultra-stable laser signal. The outcome of the project will be an integrated photonic package capable of connecting to 100 terabit-per-second networking switches over coherent optical short-reach data center fiber links. This effort could disrupt the way data centers, data center interconnects, and terabit Ethernet switches are built, drastically reducing their global energy consumption."

More information on the ARPA-E Open 2018 Program awards can be found here

The UCSB press release and statement from FRESCO PI, Professor Daniel Blumenthal, can be found here 




September 2018,
Silicon Nitride in Silicon Photonics

This Early Access Proceedings of the IEEE review article discusses the history of low-loss Silicon Nitride waveguide technology and surveys state-of-art research efforts around the globe in a variety of devices and applications with additional commentary on Silicon Nitride foundries. The full article can be viewed on IEEE Explore here.


August 2018,

Integrated combs drive extreme data rates - "A chip-based optical frequency comb source has now been successfully used to send 661 Tbits–1 over 9.6 km of multicore fibre, bringing considerable savings in the energy consumption and size of data transmission equipment"

A Nature Photonics article authored by Professor Blumenthal discusses the current state-of-art optical frequency comb-based approaches to satisfy optical fibre transmission demands for 'unprecedented bandwidths due to the explosive growth of video and Internet of Things.' This article can be viewed using the Springer Nature SharedIt link given here.


December 2017,

Professor Daniel J. Blumenthal, head of the Optical Communications and Photonic Integration (OCPI) Group, was recently named Fellow to the National Academy of Inventors (NAI).  Professor Blumenthal was cited for "demonstrating a highly prolific spirit of innovation in creating or facilitating outstanding inventions that have made a tangible impact on quality of life, economic development and the welfare of society."

The UC Santa Barbara Current article can be found here!

Optical Communications and Networks

Optical systems and subsystems

Photonic Integration

Next Generation Photonics