Optical/IP Networks

Out of the Lab: Polymer's Progress

Earlier this year, scientists at the University of Washington created quite a stir by claiming a big breakthrough in optical technology. Dr. Larry Dalton and colleagues claimed in an article published in the international journal Science that they had developed an electro-optic polymer that was miles better than other materials for making optical components.

When an electric voltage is applied to the so-called electro-optic polymer, its refractive index changes, and this effect can be used to switch light. Optical chips made from this material would be able to support transmission speeds of 100 Gbit/s, they said. The chips would use far less electrical power than existing materials, and the polymer could be sprayed onto silica to make optical circuits -- simple as that.

It all sounded a little too good to be true at the time, but in the past few weeks a startup has been formed with the goal of commercializing Dalton’s developments. The company is Lumera Corp., which has been spun out of Microvision Inc. (Nasdaq: MVIS), an outfit developing a retinal scanning platform (see Microvision Launches Spinoff).

Lumera claims to hold an exclusive license to make use of the electro-optic polymer that’s been developed and patented by Dalton and a colleague, Dr. Bruce Robinson.

Although this may be true, Dalton and his team have been working on developing organic polymers for optical components for more than 10 years -- and this isn’t the first time that Dalton has tried to commercialize his inventions. Light Reading has unearthed evidence of other companies developing components based on Dalton's earlier work in the same area.

Polymer's Big Problem

The big problem until now with using polymers for optical applications has been high losses. It's the main reason that plastic optical fiber hasn't gained any traction in the market (see Is Plastic Optical Fiber Pooping Out?). Other stumbling blocks are poor thermal and photochemical stability (sensitivity to bright light).

Dalton claims to have solved all of these problems. In the Science paper, Dalton and his associates reported a low-voltage, polymer-based optical modulator (a device that encodes an electrical signal onto an optical beam). It was the first time polymer devices had achieved bandwidths greater than 100 GHz and simultaneously kept the operating voltage below 1 volt. This result knocks the spots off devices made from lithium niobate, the material often used for making modulators. Lithium niobate modulators typically require about 5 volts and have a maximum speed of around 70 GHz.

At that point, the optical losses were still fairly high. However, Lumera's engineers now claim they have reduced losses to 0.7 decibels per centimeter, and expect to bring losses down to 0.1 to 0.2 dB/cm in the near future, which would be comparable to those of lithium niobate.

”We reckon that we can move Larry's dream to market faster than a big company," says Matt Nichols, Lumera's director of corporate communications. The commercialization of Dalton’s developments will be helped along the way by other developments, notably packaging processes which now don't need such high temperatures. As noted, however, Lumera isn't the only company working on electro-optic polymers. Two of the authors on the Science paper, Yongqiang Shi and James Bechtel, work at Ipitek Inc., a Carlsbad, Calif., firm. Ex-UW researcher Shi started the collaboration by bringing some of Dalton's materials with him when he joined Ipitek. (Shi has since moved again, this time to Lucent Technologies Inc. [NYSE: LU], according to an article in the San Diego Union Tribune.)

Another manufacturer, Pacific Wave Industries Inc., says it has already released products based on Dr. Dalton's polymer. (Pacific Wave's web site doesn't explicity name Dr. Dalton, but it does say that the material was developed at the University of Southern California, where Dr. Dalton also works).

In an e-mail to Light Reading Dr. Dalton explains how more than one company can claim to have an exclusive license. "Lumera has rights to current and future materials produced in my laboratory by agreement negotiated with the University of Washington. Other companies have received older materials," he says.

According to Dr. Dalton, the companies and Federal Labs that have received older materials include the Air Force Research Laboratory (AFRL), Ipitek Inc., KVH Industries Inc., Lockheed Martin Corp., Lucent, Pacific Wave, the Navy China Lake Weapons Laboratory, the National Institute of Standards and Technology (NIST), Radiant Research Inc., Redstone Arsenal, and others.

Dalton adds "It's worth pointing out that electro-optic polymer materials keep improving. We have already dramatically exceeded the performance of the material that was the subject of the Science article. In fact, at the time of the article, Lockheed Martin managed to equal our result, using another material developed at UW."

The interesting question is just how far electro-optic polymer materials will improve. Dalton doesn't know the answer but reckons it could be truly revolutionary. "Developments are guided by new condensed matter theory (as explained in the Science article) which predicts that further dramatic improvements could be achieved," he says. As the only company with a license to future patents, Lumera is in a good position.

-- Pauline Rigby, senior editor, Light Reading http://www.lightreading.com

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