Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Printed Photonic Crystal Mirrors Shrink On-Chip Lasers Down to Size

24.07.2012
Electrical engineers at The University of Texas at Arlington and at the University of Wisconsin-Madison have devised a new laser for on-chip optical connections that could give computers a huge boost in speed and energy efficiency.

The team published its findings on July 22, 2012 in Nature Photonics.

At just 2 micrometers in height – smaller than the width of a human hair – the surface-emitting laser's vastly lower profile could make it cheaper and easier for manufacturers to integrate high-speed optical data connections into the microprocessors powering the next generation of computers.

Traditionally, edge-emitter lasers are considered as the candidate for on-chip optical links. But since mirrors are hard to form in such lasers and because the lasers occupy a large chip area, researchers have been challenged to find a practical way to monolithically integrate the mirrors on silicon chips.

Surface-emitting lasers necessary for a high-speed optical links between computer cores could be 20 to 30 micrometers tall, slightly bigger than one hole in the mesh of a car’s oil filter. Yet the research team’s engineers say that on a 1.5-micrometer wavelength optically connected chip, lasers of that size dwarf their silicon surroundings.

"It sits tall on the chip, like a tower,” says Zhenqiang Ma, a UW-Madison professor of electrical and computer engineering. “That is definitely not acceptable."

Weidong Zhou, a UT Arlington professor of electrical engineering, says one challenge was integrating light into silicon chips, as silicon itself is not an efficient light emitter.

Zhou and Ma have collaborated to shrink on-chip lasers in recent years with funding from the U.S. Air Force Office of Scientific Research, Army Research Office and Defense Advanced Research Projects Agency.

As a solution, the researchers propose replacing layers and layers of reflectors necessary in the traditional distributed Bragg reflector laser design with two highly reflective photonic crystal mirrors. Composed of compound semiconductor quantum well materials, each mirror is held in place with silicon nanomembranes, extremely thin layers of a silicon.

Zhou says integrating compound semiconductor quantum wells with silicon is a promising approach. “We apply a nanomembrane transfer printing process to accomplish this goal,” he says.

One layer of photonic crystal is equal to about 15 to 30 layers of dielectric reflectors found in conventional lasers. As a result, manufacturers could fabricate 2-micrometer-high lasers for data links with performance that could equal current designs.

In addition to their larger size, reflectors for conventional lasers are made of materials grown only at very high temperatures, which means they can damage the chip they are placed upon during production. Since fabrication via transfer printing can occur at much lower temperatures, Zhou and Ma hope their laser design can be used to place optical links on silicon chips with much less wasted material, time and effort.

Optical data links already exist at the largest scales of data networks – the Internet’s backbone is composed mainly of fiber-optic links between countries, cities and houses. But currently, that data moves over to slower metal connections and wiring as it travels from a regional hub to your house, your computer and eventually between the CPU cores within of the processor powering your machine.

“In the future, you'll see a move to optical at each step,” Ma says. “The last step is within the chip, module to module optical links on the chip itself.”

Through Semerane Inc., the Texas-based startup Zhou and Ma founded, the two hope to implement their production process in functional on-chip photonic crystal membrane lasers that could eventually be part of the next generation high-speed computer processors.

“We believe this laser will be used to make data links more practically available,” Ma says.

“It is truly an interdisciplinary team effort,” Zhou says. “The co-existence of photonics with electronics on the chip level shall enable multi-functional energy-efficient super-chips for applications in computing, communications, sensing, imaging and so on.”

With widespread adoption of processors that use their laser design for optical links, Ma and Zhou could have a hand in increasing the speed along the local leg of the information superhighway.

“Eventually, a CPU core in America could be connected to another CPU core in Asia, with optical connections all along the chain,” Ma says.

Read the full paper here: http://dx.doi.org/

—Mark Riechers, mriechers@engr.wisc.edu, 608-265-8592
—Herb Booth, hbooth@uta.edu, 817-272-7075

Zhenqiang (Jack) Ma | Newswise Science News
Further information:
http://www.wisc.edu

More articles from Power and Electrical Engineering:

nachricht Solar-to-fuel system recycles CO2 to make ethanol and ethylene
19.09.2017 | DOE/Lawrence Berkeley National Laboratory

nachricht A simple additive to improve film quality
19.09.2017 | King Abdullah University of Science & Technology (KAUST)

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

Im Focus: Silencing bacteria

HZI researchers pave the way for new agents that render hospital pathogens mute

Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...

Im Focus: Artificial Enzymes for Hydrogen Conversion

Scientists from the MPI for Chemical Energy Conversion report in the first issue of the new journal JOULE.

Cell Press has just released the first issue of Joule, a new journal dedicated to sustainable energy research. In this issue James Birrell, Olaf Rüdiger,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

New quantum phenomena in graphene superlattices

19.09.2017 | Physics and Astronomy

A simple additive to improve film quality

19.09.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>