Biomimetics.” Say it three times. Then, try to type it. If your tongue doesn’t trip you up, your spell-checker certainly will.

It sounds a little forced at first, but really biomimetics is the study of nature: understanding what nature does well, and applying those engineering principles to manmade devices.  This is something humans have been doing throughout history, at least informally. Think about flight.  Would we have airplanes today without the engineering inspiration of birds?

In the last 10 years, this type of research has really taken off.  Today, Bell Labs is home to some of the most innovative biomimetics research going on anywhere in the world.  Our researchers are looking at organisms with special properties, such as fiber optics, for insights and discoveries that could one day lead to enormous improvements in the manufacturing of materials, devices, and technologies.  Such improvements could include cost savings, higher capacity, improved efficiency, stronger structures, and better manufacturing processes in everything from lenses to fiber optics to nanomaterials. 

Bell Labs’ Joanna Aizenberg, a member of technical staff in the Labs’ Materials Research department, recently talked about her work in biomimetics. 

Please tell me a little about your work.

I look at nature and try to understand it, and use natural strategies and materials to improve existing artificial materials and devices. My work is in the area of biomimetics.  The goal of biomimetics is to “mimic” natural products and processes.  Biology gives us so many interesting biological systems that possess exciting properties, so we must first decide what to study. My group at Lucent is most interested in biological systems with components that can be directly applied to the technology and telecommunications industries, such as highly structured nanomaterials or natural solutions to optic or magnetic problems. 

The second step is to identify and understand the underlying mechanisms of natural systems:  What are the solutions and materials that nature uses? What problem does the system solve? How does it solve that problem?  These questions are largely in the fundamental science domain, but the findings are related to the applied side of biomimetics: After we understand nature, then we formulate principles and use them in technologies, and in artificial materials and devices. That is our ultimate goal.

What have you learned from nature?

Several years ago, we discovered thousands of chalk-like calcite crystals spread throughout the exoskeletons of brittlestars, which are starfish-like marine invertebrates. Using naturally formed microlenses, the crystals collectively form an unusual compound eye for the animals. We are now developing synthetically made microlenses, based on our insights from studying brittlestars.  We published our findings in a well-received study in Nature.

Can we apply these findings to improve technology?

We are looking at how to use our brittlestar findings in technology.  We are making lens arrays – from artificial materials – but duplicating nature’s brittlestar design, which integrates optics and microlenses with microfluidics, which is the study of fluids on a very small scale.

Instead of unchangeable lenses, the brittlestar uses a channel microfluidics system through which it pumps pigments to cover the lenses during the day, when there is too much light. Those pigments serve as sunglasses for the organism, enabling the brittlestar to modify and control the amount of light that comes through the lenses. That active transfer of pigment is exactly what we want to mimic.  We want to combine lenses with microfluidic systems through which we can pump liquids.  By doing this, we could drive liquids through the porous arrays and make lenses that are tunable and responsive to external stimuli, instead of the rigid lenses with fixed optical properties that are manufactured today.  We have a patent for tunable dye filters based on our brittlestar work.

Why are tunable lenses a good thing?

The ability to adjust the transmission of light through lenses is beneficial because conditions are different everywhere and always changing.  By pumping in liquids that are sensitive to a specific wavelength, we can dynamically adjust the system, and use the same array for different functions -- changing the function by what we pump into it.

These lenses might also be positioned on a curved and flexible surface, so they could be oriented in different directions.  That can be accomplished by using flexible materials, something that nature does very well. 

The range of applications that one can imagine for tunable lenses is very large.  As a result of this work, we now have patents and patent applications in tunable lens technology that are based on biological principles. 

What did you learn from your work with the Venus Flower Basket?

We made a substantial discovery studying biologically formed fiber-optical systems in the Venus Flower Basket, which is a deep-sea sponge. We knew that the organism had an intricate skeleton of glass. But no one expected that sponges could have fiber-optical properties.

At the base of the sponge’s skeleton is a tuft of beautiful fibers that extends outward like an inverted crown.  We discovered the organism uses this bundle of glass fibers to distribute light and act as a beacon to attract prey and organic matter.  This is very interesting in general.

From a technological standpoint, however, we wanted to get a deeper understanding of how nature forms these optical fibers, because they have many properties that are better than commercial fibers.

First, they are formed at ambient temperatures.  The sea sponge makes its glass fibers at about zero degrees Celsius instead of requiring a 2,000 degree furnace to stretch glass into the desired fiber, which is the way optical fibers are created today.  Imagine if we could manufacture optical fiber at room temperature without a clean room.  We would have enormous advantages in terms of saving energy and money, and using less harsh chemicals.  It would be a great way to go.

In addition to making optical fibers at low temperatures, nature makes glass fibers that are up to a hundred times stronger than the glass fibers we make. We may need years and years of research to understand how nature makes high quality glass with optical properties, but if we can do it, there would be a huge payoff at the end.

What else did you learn from the study of these sea creatures?

Both the brittlestar and the sponge give us a great idea that is not commonly used yet in technology: multifunctionality.  In both cases, the primary function of the skeleton is to be mechanically strong. But at the same time it has another optical function.  This is a great lesson for us. In the future, we should mimic nature and design materials and devices that serve multiple functions. 

Mechanics and nanomaterials design is another interesting area.  In the sea sponge, we identified seven different layers of structural hierarchy.  The sponge uses all of the reinforcement mechanisms that we know and use on the macro scale when we build buildings or bridges, but all in one structure and on a scale that is at least a thousand times smaller than a building.  It makes the design nearly unbreakable – the strongest glass design one can imagine. So this gives us a lot of ideas that we can use in construction, in making nanomaterials [materials on the atomic and molecular scale], and making macromaterials [very large materials] out of small components. 

Last but not least, we are using what we learned so we can grow materials the way nature does: from the bottom up. Today lenses are typically made using a "top-down" approach, in which a piece of glass is ground down to a lens' exact specifications. The brittlestar, on the other hand, makes its microlenses using a "bottom-up" approach, in which successive layers of calcite are deposited onto an organic template in intricate patterns to form perfect crystalline lenses at the temperature of seawater. Nature grows materials in their final form.

Is anyone using bottom-up manufacturing now?

Not yet. We at Bell Labs are some of the pioneers of this biocrystal engineering work. Again, the idea is to use biological principles.  In this case, that means using proteins so that you can then use bioorganic material and be very selective, depositing an organic catalyst to define where the crystal will grow, for example.  Instead of slicing a crystal and making it into the shape you want, it grows into the final shape, at ambient temperatures, and nothing else has to be done. In 2003, Bell Labs provided the first demonstration of how to grow single crystals with nano-scaled features in this bottom-up fashion.

How far has the field of biomimetics come since Lucent’s inception?

Work and interest in the area of biomimetics have increased exponentially since Lucent was born.  People are realizing the importance of this field. In most areas of research, you never know if your research will lead to any new developments. When we study a structure in nature, we already know it works, because it works in nature. It’s just a matter of learning how.

For example, we started to look at microlenses in biological systems in 1999.  In 2001, we published a paper on the topic – about biology – no relevance yet to any applied studies. By 2005, we’d published five papers on applications of this research.  In just four years we went from purely fundamental research looking at biological systems to making prototypes of tunable optical devices that were based on biological structures. 

Where do you see your work going in the next 10 years?

It may take another 5 to 10 years before tunable optics will be used in devices – maybe a little bit more.  My vision of this field is that we do not want to replicate exactly what nature gives us.  Making a “synthetic brittlestar” is not our goal.  That could take a century. But we can break the beauty and intelligence of the biological world into incremental steps, and these we can bring to technology. 

Within five years we went from fundamental biological research to application.  As more and more studies in this area appear, we will do it even faster than that.  We will reach a stage where we have an exponential number of breakthroughs in the understanding of biological systems that can be put into practice.

Why is biomimetic research important for Lucent?

There are a number of reasons biomimetic research is important to Lucent.  Bell Labs has a tradition of both fundamental and applied research. Fundamental research is important because it provides the basis for tomorrow’s innovations. Today’s basic scientific breakthroughs may not have immediate impact, but could create new markets, new devices or new technologies in the future.

Second, within a very short period of time we were able to apply what we learned. We have a growing portfolio of intellectual property in this area. 

Third, will we see a product from this research? I can’t promise that. But we are sharing what we learn with our engineers, and in fact I am called upon to collaborate on other projects within the Labs all the time.

As a scientist, I find that it is interesting to see how my research can be used by product developers.  This is a long-term research project with the potential of changing and revolutionizing the technological processes.

Because it is a very young science, we are still at the level of prototype development:  proof of principle.  The last 10 years have been quite successful to show that there is potential in this field. How long will it take to go from proof of principle to real devices? It is hard to tell.

What is your favorite thing about studying nature?

It combines the beauty of fundamental science with the excitement of life science. It is one of the most multidisciplinary sciences that exists these days.  I collaborate with biologists, chemists, material scientists, physicists and engineers, because without the help of people from different backgrounds, you cannot address problems that are this complex.  It is fascinating and stimulating to have a multidisciplinary group of people addressing the same issue.

I also like that it is full of surprises. Nature does not always give us what we expect.  Some of the best things I’ve learned are the result of branching out from the mainstream, when I was looking into one thing and then something else appeared interesting, so I went along. I’ve learned to welcome surprises.  They often provide insights that are beyond anything we could imagine.