From the Special Topic of
In our analysis of research on photonic crystals
in the past decade, the work of Professor Jonathan Knight
ranks at #3 by total cites, with 78 qualifying papers cited
a total of 3,012 times. Two of these papers also appear on
the list of the top 20 papers in this topic. In
Science IndicatorsSM from
Reuters, Prof. Knight's record includes
196 papers, the majority of which are classified in the
fields of Physics or Engineering, cited a total of 6,371
times between January 1, 1998 and June 30,
Prof. Knight hails from the University of Bath, where he is Head
of the Department of Physics and member of the Centre for Photonics and
In the interview
below, ScienceWatch.com talks with Prof. Knight
about his highly cited research on photonic
Please tell us a little about your
research and educational background.
I did my Ph.D. in Cape Town, South Africa, during the dying years of the
apartheid government. It was an exciting time and place to be in a liberal
university environment, but very isolated both politically and
geographically. The realization that one could communicate intellectually
on a global scale through published work was a real eye-opener for me.
"Ph.D. student Jim Stone doing the work
described in the recent Optics Express
paper as described in the text."
My Ph.D. was on microlasers, and I’ve been interested in trapping
light in confined spaces ever since. I did postdoctoral research in Paris
before moving to the United Kingdom in 1995.
Your most-cited original paper in our analysis is
the 2000 IEEE Photonics Technology Letters article,
"Anomalous dispersion in photonic crystal fiber," (12: 807-9, July
2000)? Would you talk a little bit about this paper's methods,
findings, and conclusions?
The paper demonstrated that one could design and fabricate optical fibers
with properties which had previously been unobtainable. We proved
experimentally that a very simple model of the fibers gave reliable
predictions of their properties. The paper had a big impact because it
showed that very simple physics combined with a straightforward fabrication
process opened the door to a range of possibilities which had not
previously been explored.
Based on the number of papers in your publication
list, photonic crystal fibers are a prominent theme of your research.
Why is this—what makes them so interesting to you and to the
field at large?
Photonic crystal fibers are interesting for many reasons, but the one that
always strikes me is that by forming microstructure in naturally occurring
materials, one can create synthetic optical materials which have unique
characteristics. We can relatively easily create optical effects which have
probably not occurred before in the history of the universe! There is
another side to the fiber work: optical fibers are an important part of our
global society, and that makes research into them of interest both for
applications and also for educational reasons.
One of your more recent papers is the 2008
Optics Express article, "Visibly 'white' light generation in
uniform photonic crystal fiber using a microchip laser," (16: 2670-5,
2008). Would you sum up this paper for our readers?
"Creativity is everything—we
are only limited by our
This paper shows how one can design a better supercontinuum fiber, and why
it is better. Light traveling in these special fibers can change color as
it travels, and a length of a few meters of fiber can transform an infrared
laser beam into a brilliant rainbow of light spanning the visible and
infrared. By modifying the fiber design, we show how to generate shorter
wavelengths than before, extending into the ultraviolet. The design has
been licensed to a laser company, and is already integrated into one of
How far has this work come since you entered the
field? Where do you see it going in the next decade?
When I entered this field it was little more than an idea dreamed up by my
colleague Philip Russell. It has become a well-funded and exciting research
topic, with major efforts across the globe. There are great opportunities
for doing novel nonlinear optics and atomic physics in new and unexplored
environments, and I am sure some major discoveries remain to be made in
this area. Some of the most exciting work at the moment is
application-driven, because we have the chance to affect whole industries
of the future. In particular, I expect to see an impact on biomedical
analysis, and on laser design and use.
What should the "take-home" lesson be about your
Creativity is everything—we are only limited by our imaginations.
There are always new things to do, but although they are right in front of
us they can be hard to see. I also believe that enjoying your work is
vital, and if you are not having fun you should be doing something
Jonathan Knight, Ph.D.
Department of Physics
Centre for Photonics and Photonic Materials
University of Bath
Keywords: photonic crystal fibers, optical fibers, synthetic
optical materials, supercontinuum fiber, laser