Outstanding Master’s Thesis at the Department of Physics Honored

From left to right: J. Javaloyes, Thomas G. Seidel y Svetlana V. Gurevich

Caption: From left to right: J. Javaloyes, Thomas G. Seidel y Svetlana V. Gurevich

Infineon Master Award 2021″ goes to Thomas Seidel

Thomas Seidel has received the “Infineon Master Award” worth 1,500 euros, for his outstanding master’s thesis on nonlinear laser dynamics directed by Prof. Julien Javaloyes at the University of Balearic Islands (UIB) and Dr. Svetlana Gurevich at Westfälische Wilhelms-Universität (WWU) Münster, Germany.

His results were found to go far beyond the scope of a master’s thesis and to be scientifically original and of very high quality [1].

The 25-year-old physicist is continuing his scientific career with a PhD at the Institute of Theoretical Physics at WWU in the group of Dr. Svetlana Gurevich and at the Departament de Física & IAC-3 of the University of the Balearic Islands under the direction of Prof. Julien Javaloyes.
Improving optical data communication and medical imaging

Nonlinear laser dynamics combines methods from nonlinear dynamics and laser physics to study, for example, dynamic instabilities that can arise in lasers. This research area is particularly relevant for controlling, manipulating and optimizing so-called semiconductor lasers. Among other things, they are needed for data communication with light pulses or for medical imaging.

Effects of feedback on light pulses

In his master’s thesis, Thomas Seidel theoretically investigated how time-delayed feedback affects the behavior of short light pulses. With his calculations, he showed that the feedback is visible in the form of small satellite pulses before and after each main light pulse. The position of the satellite pulses can be controlled by the delay time, while the size is determined by the feedback rate.

If the satellite pulses are placed very close to the main light pulse, they can even lead to its destabilization: Thus, above a certain threshold, the satellite pulses successively replace the main light pulse. This so-called satellite instability has only recently been demonstrated experimentally. With his master’s thesis, the physicist has discovered a highly relevant instability mechanism.


[1] “Manipulation of temporal localized structures in a vertical external-cavity surface-emitting laser with optical feedback”

A. Bartolo, T. G. Seidel, N. Vigne, A. Garnache, G. Beaudoin, I. Sagnes, M. Giudici, J. Javaloyes, S. V. Gurevich, and M. Marconi

Optics Letters Vol. 46, Issue 5, pp. 1109-1112 (2021)