麻豆淫院

(麻豆淫院Org.com) -- We use lasers everyday, though many of us may not think about it. 鈥淟asers are in a number of consumer products,鈥� Lynford Goddard tells 麻豆淫院Org.com. 鈥淲e have them in DVD players, printers, and in other products.鈥�

Right now, many consumer products make use of linear Bragg reflectors for laser mirrors. However, as a desire for ever-smaller and more complex devices pervades society, some of these conventional lasers are too big to densely pack in a photonic integrated circuit. 鈥淥ur goal originally was just to make a smaller device. We took the conventional linear Bragg reflector and rolled it on itself to save space,鈥� Professor Goddard explains. He worked with Amir Arbabi, Young Mo Kang, Ching-Ying Lu and Edmond Chow at the University of Illinois at Urbana-Champaign to create a design integrating a distributed Bragg reflector inside a microring resonator.

鈥淲hat we found,鈥� Goddard continues, 鈥渨as that our geometry solved other problems associated with the linear distributed Bragg reflector. Not only did we make a smaller device, but we were also able to engineer a more ideal spectral response. It was narrower and free of side mode ripple.鈥� The results of the team鈥檚 work can be found in Applied 麻豆淫院ics Letters: 鈥淩ealization of a narrowband single wavelength microring mirror.鈥�

鈥淏ragg reflectors are found in telecommunication systems, sensors, diagnostic equipment 鈥� including medical equipment, as well as in consumer products,鈥� Goddard says. 鈥淥ne of the issues, though, is that you can get 鈥榤ode partition noise鈥� because there are several different wavelengths competing for power due to side mode ripple. Our design is such that only a single wavelength is strong. The other wavelengths are there, but they are greatly suppressed. This reduces noise, and allows for better spectroscopy, and would also be ideal in telecommunications applications.鈥�

Microring resonators aren鈥檛 new. 鈥淭his is a well-known device,鈥� Goddard says. 鈥淗owever, we added the Bragg reflector, patterning it along a specific fraction of the circumference of the ring. This is what allows it to be reflective at exactly one resonance and not others.鈥�

Goddard and his colleagues created the reflective microring structure using common materials. 鈥淲e used materials already common in the semiconductor industry,鈥� he explains. 鈥淭he real novelty is in terms of device design.鈥� Using materials that are already common and accessible also increases the chance that this new version of reflector could be put into wider use sooner than a device that requires the development of new materials.

Graduate student and lead author Amir Arbabi describes the long process involved in realizing this novel device: 鈥淲e quickly developed an intitial device model, and then spent over two years refining it, developing new simulation methods, writing proposals to support the research, perfecting the fabrication process, and building the testing station.鈥� He is also quick to point out that the work received the support of a NSF grant.

鈥淓ven though our original goal was to simply create a way to shrink laser devices, there are a number of uses for this design,鈥� Goddard insists. The improved performance, along with the smaller size, is a real advantage. 鈥淭his device will also be useful in metrology, medicine and telecommunications as well as in consumer products.鈥�