Improved design of lasers on optoelectronic chips will advance optical communications
When it comes to data transmission, light is superior to electronics. An ability to transmit data in parallel by utilizing multiple light wavelengths allows optical fibers to carry more information than electrical cables.
Current computer technology uses electronics, but a new laser design based on a thin-layered silicon chip may help increase data processing capabilities.
© Olga Miltsova/Hemera/Thinkstock
Computers are currently based on electronics, but they would benefit from employing optical signals. However, for this to become a reality, it needs to be implemented on a small scale and result in low power consumption.
Now, Vivek Krishnamurthy from the A*STAR Data Storage Institute in Singapore and his colleagues have designed a laser on a microelectronic chip that has a lower power consumption and a higher efficiency1.
“By developing lasers on silicon, we can combine the electronic data processing capability of the microelectronic chip with the high energy efficiency of optical communications over distances ranging from a few micrometers within a chip to hundreds of meters in data centers,” says Krishnamurthy.
The processing speed of the microelectronic chip is limited by its power consumption; most of the power is consumed by the connecting electrical wires and links. Optical links, on the other hand, consume practically no energy but are limited by the power consumption of the light source, which is often a laser.
For optical links to be feasible on a small scale, the electrical power consumption of lasers must be reduced, yet still be able to generate sufficient optical energy for transmission.
Lasers cannot be made from silicon as it is a poor light emitter. Instead, lasers are fabricated by bonding an active material based on indium phosphide — a good light emitter — to a thin silicon film. However, because silicon is better for carrying optical signals, the light from the laser needs to be routed through the silicon chip via optical channels. This requires fabricating optical channels in silicon outside the laser region.
Generating light efficiently in the active medium and efficiently routing it via the silicon layer simultaneously reduces the electrical current required and increases the power generated. Calculations show that this silicon-based design will have a three to four times higher light generation efficiency than competing schemes.
This high efficiency makes the silicon-based laser design promising for making optical chips, which, says Krishnamurthy, is the next step for the project team. “We have begun the experimental demonstration of the laser,” he says. “Our plan is to integrate this laser onto our silicon platform and develop a fully functional photonic system for applications, for example, in data communications and storage.”
The A*STAR-affiliated researchers contributing to this research are from the Data Storage Institute
Krishnamurthy, V., Wang, Q., Pu, J., Loh, T.-H. & Ho, S. T. Optical design of distributed feedback lasers-on-thin-film-silicon. IEEE Photonics Technology Letters 25, 944–947 (2013).
A*STAR Research | ResearchSEA News
First machine learning method capable of accurate extrapolation
13.07.2018 | Institute of Science and Technology Austria
A step closer to single-atom data storage
13.07.2018 | Ecole Polytechnique Fédérale de Lausanne
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
13.07.2018 | Event News
13.07.2018 | Materials Sciences
13.07.2018 | Life Sciences