Meet a PhD graduate: Development of dynamic optical fibers

Thomas Tanggaard Alkeskjold
Research Scientist/Project Manager with NKT Photonics
M.Sc. from DTU and PhD from DTU Photonics
Spare-time recreation: Sailing when wife and two children, new house and work allow for it.
Age: 34

In 2005 Thomas Alkeskjold finished his PhD project: Optical devices based on liquid crystal photonic bandgap fibers, and in 2006 Lars Pallesen, University President, presented him with Managing Director Peter Gorm-Petersen’s memorial grant for his work. Thomas Alkeskjold continued in a post doc position at DTU Photonics, and in 2007 Helge Sander, then Minister for Science, Technology and Innovation, presented him with the ministry’s award ”Young Elite Researcher”. Later in 2007 Thomas Alkeskjold started working with the former Crystal Fibre, now NKT Photonics A/S which was the result of the merger between Crystal Fibre and Koheras in 2009.

When did you first become interested in optical fibres?

Relative early during my studies when I had a job as a student with an electronics company that worked on integrating fibre optics into communication systems. I discovered the possibilities of fibre optics and at the same time I met my then to be PhD supervisor professor Anders Bjarklev who was very enthusiastic about the new technology and who moreover made me realize the great potential of this area. Soon a group of 6-8 individuals emerged at DTU Photonics; all worked with optical fibres and it was a great help always to have someone to exchange ideas and experiences with. NKT very soon became interested in going into close collaborations. For us at Photonics this meant that we always had access to the fibres and other materials we needed for our tests.

So you had already had contact with NKT/Crystal Fibre when you were working on your PhD project?

Yes my PhD studies were a little unusual as they were partly financed by a stipend from NKT Academy, so the connection was there from the beginning. My project dealt with building functionality into optical fibres so that instead of using the ordinary static optical fibres which transport light from A to B, then you could filter and turn light in a number of brand new ways. At that time when you needed functionality in light, you had to, plainly speaking, first take the light out of the fibres, filter it and put it back into the fibres again. The intention of my project was to achieve the desired functionality but with removing the light from the fibres, and I actually succeeded in this, against all expectations. The work I began in 2002 has thus been in progress for eight years and new PhD students at DTU are currently carrying on and further developing the methods which I tested in my project. Today I act as external advisor for these students, and I am very impressed with how good their results are. It is especially encouraging to see how much the overall research progress has made an impact internationally and to see that the results are cited widely in the important scientific journals.

And you still work within the same field in your current job?

Yes, even though focus has moved somewhat, the focal point is still optical fibres. My current work mainly revolves around specialized optical fibres in continuation of a development that was actually started by Anders Bjarklev 10-12 years ago at DTU. There is an enormous market for laser fibres, and together with a number of other colleagues, I am developing the technology which should preferably be the one to cover this market. With the new fibres it will be possible to control light in completely new ways. For example by using light for building the fibres instead of glass which was used earlier, we achieve an even better control of light and more freedom in the design of the fibres. The ultimate goal for us is to become leading suppliers of fibres for the laser market, and then to begin manufacturing the lasers ourselves within the next three to five years.

Do you benefit from having a PhD in your day-to-day work?

It has been extremely useful for me to go through the PhD studies. In NKT Photonics we develop advanced and immensely complicated fibres and our focus is on incorporating all functions into all these fibres. It is extremely research heavy work to make fibres functional, and I would never have been capable of performing this work without the foundation of my PhD.