Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Photonics: Integrated laser on silicon is looking good

29.03.2012
A unique 'micro-loop mirror' design may enhance the performance of integrated laser on silicon
Active optical fibers with silicon photonic chips can carry a lot more information for data interconnect than copper cables. Silicon photonics can also be the material of choice for wiring 'lab-on-a-chip' devices — however, the construction of such devices is not without its challenges. One of the greatest difficulties is the implementation of lasers because silicon is a poor light emitter, but is commonly required for a photonic system on chip.

Doris Keh-Ting Ng at the A*STAR Data Storage Institute and co-workers have now successfully fabricated a laser on top of a silicon chip1. The III-V semiconductor materials are bonded to silicon to provide optical gain and the laser has a unique mirror design that promises enhanced device operation compared to the conventional feedback mirrors based on device facets.

“Integrated Si/III-V lasers can take advantage of low-loss silicon waveguides, while addressing the problem of low light emission efficiency that silicon devices typically have,” says Ng. Attaching a Si/III-V laser on top of silicon requires challenging fabrication techniques, and device performances can suffer as a result. Furthermore, any laser requires mirrors to maintain lasing action. Typically, such designs rely on the interface between air and the semiconductor, that is, the facets of the chip. These mirrors are not perfect and further reduce operation efficiency.

To improve on the latter aspect, the researchers have now come up with a unique mirror design, known as a micro-loop mirror (MLM). Light emitted from one end of the laser is guided along the waveguide, around a narrow bend and is then directed back into the device (see image). The mirror at the other end of the device is still formed by the interface with air, so that laser radiation can exit the device. The MLM achieves a remarkable 98% reflection efficiency of light. Such low losses mean that the MLM laser is comparatively efficient.

The successful demonstration of this technique is remarkable, considering that more than 30 fabrication steps are needed to fabricate the device, and in view of the fact that the MLM requires delicate and high-precision fabrication. The researchers aim to further enhance the laser, for example, by miniaturizing the device.

“Further improvements, for example, at the interface between the mirror and the lasing structure itself could lead to even better performance,” says Ng. “Laser with lower threshold and higher output power can possibly be achieved, leading to a potential solution to develop high-speed and low-cost optical communications and interconnects on electronics chips.”

Scanning electron microscope image of the silicon-based micro-loop mirror. Light entering the waveguide from the left is guided around the loop and redirected back into the laser structure. The inset shows the laser spot photographed with an infrared camera. Copyright : A*STAR

The A*STAR-affiliated researchers contributing to this research are from the Data Storage Institute

Lee Swee Heng | Research asia research news
Further information:
http://www.research.a-star.edu.sg

More articles from Physics and Astronomy:

nachricht Breakthrough with a chain of gold atoms
17.02.2017 | Universität Konstanz

nachricht New functional principle to generate the „third harmonic“
16.02.2017 | Laser Zentrum Hannover e.V.

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Switched-on DNA

20.02.2017 | Materials Sciences

Second cause of hidden hearing loss identified

20.02.2017 | Health and Medicine

Prospect for more effective treatment of nerve pain

20.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>