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