Image: Sophie Viaene and Ferry Nugroho
Sophie Viaene and Ferry Nugroho wrote the best doctoral theses at the Department of Physics at Chalmers in 2018. ​​​​​​​​​​​​​​​​​

Writing a successful PhD thesis: They know how to find the flow

Writing a doctoral thesis is a complex task. Besides the requirements of high scientific and pedagogic quality, a thesis should also be accessible to the reader. At best, it should be enjoyable to read – like a well written novel. But how do you do it? We asked Sophie Viaene and Ferry Nugroho, who wrote the best doctoral theses at the Department of Physics at Chalmers in 2018.
Sophie Viaene:

“Doing science is like making a journey”

Sophie Viaene has used techniques from general relativity, condensed matter physics, and nonlinear dynamics to describe advanced electromagnetic phenomena inside structured artificial materials, so called metamaterials. By controlling the behaviour ​of light inside such materials, her work paves the way for future light-based applications. For example, the materials can be used in optical chips to achieve reliable data delivery on the internet, or to speed up routers.

 
Sophie Viaene has been a double degree doctoral student at Chalmers and Vrije Universiteit Brussel. She had an open thesis review at Chalmers in May 2018, followed by the thesis defence in Brussels in June.
The title of her work is Exploring metamaterial horizons:  New concepts and geometrical tools for the description of advanced electromagnetic phenomena.

 
 “Sophie definitely deserves the award: for her PhD she has solved multiple challenging problems in the field of electromagnetic structured materials, which has only been possible because of her smart and creative use of theoretical and computational tools. In addition, she has written an exceptionally beautiful thesis. I am very proud of her,” says Sophie Viaene’s supervisor Philippe Tassin, Associate Professor at Department of Physics at Chalmers. 

 
 “I am very honoured by this award. To be highlighted among the many exciting physics projects at Chalmers by an independent panel of physics professors is something that I am very proud of, " says Sophie Viaene.  
What do you think made your thesis so appreciated?
“I think that my thesis was appreciated because it combines ideas from quite a few scientific disciplines. In our field, the main focus is often on the design of a specific type of artificial metamaterials that control light to a high precision by making use of small engineered structures. Our aim was not to develop specific material designs, but to more generally explore what are the physical restrictions on possible applications with metamaterials, hence the title of my thesis “Exploring metamaterial horizons”.
A second reason why I think that my thesis stood out is because of how I have visualized and communicated the research in the form of a monograph. I did enjoy the process, because it allowed putting things into context and visualizing the research in a way that is different from the research papers.”
What was the hardest part of the work?
“The coolest and hardest question we were trying to answer is whether metamaterials can behave as artificial black hole analogues. Real black holes are massive objects that deform space and time in an extreme way, for example, time slows down close to the event horizon of a black hole from which nothing can escape, not even light. I really struggled to find how photons behave near this singularity. It took several approximations, some clever analytics, quite a lot of numerics, and a year and a half of dedication, to find out exactly how metamaterials change the notion of space and time.”
… and the best part? 
“Professor Uri Alon has a TED talk that nicely captures what I think is the best part of doing a PhD. He explains that doing science is similar to making a journey, starting from a known point A and planning to go to point B. Instead, one ends up getting stuck in a “cloud” of challenges, uncertainties, and maybe even inconsistencies, before emerging from this cloud to point C that is quite different from B. The last year of the thesis was the best part, when finishing up and realizing how things have worked out.”
What piece of advice could you give to future doctoral students?
“Two things have been crucial for me: Interacting with my supervisors and colleagues (try to find a group with nice atmosphere and a sense of sharing) and having chosen a scientific discipline that matches with my research preferences, in my case a young scientific discipline with plenty of opportunities for new methods and ideas. So, my main advice is: choose wisely! "
What are you up to now?
“I am a postdoctoral researcher at Imperial College (the Ortwin Hess group), focussing on the design of small nanolasers without a cavity.”

 
 
 
Ferry Nugroho:

“I wanted my thesis to be approachable by all readers”​


​​​​

"Imagine driving a car for hours, travelling along the beautiful coasts of Sweden, and what is coming out of the exhaust pipe are not toxic and polluting gases but only water". That is how the abstract ​of ​Ferry Nugroho's thesis starts. He has developed a hydrogen detection platform that uses light and alloy nanoparticles to create fast, sensitive, and stable hydrogen sensors. Such sensors are essential to ensure that future hydrogen vehicles are safe enough.
 
Ferry Nugroho defended his doctoral thesis at the Department of Physics at Chalmers in May 2018. The title of his thesis was Nanoplasmonic Alloy Hydrogen Sensors A Quest for Fast, Sensitive and Poisoning-Resistant Hydrogen Detection

 
”Ferry’s work is not only very comprehensive and diverse, it also constitutes a true breakthrough in hydrogen sensor technology, which was achieved through his efforts to first understand the limiting factors at the fundamental level, and then systematically mitigate them," says his supervisor Christoph Langhammer, Associate Professor at the Department of Physics.
 
“I am very surprised and honoured. It is great that the thesis is appreciated, and I hope it is useful for both scientific and education reasons,” says Ferry Nugroho. 
What do you think made your thesis so appreciated?
“I was aware before writing that I'd like to write a thesis that is approachable by all readers, skilled or not. So, I avoided too deep discussions on the physics and whatnot and tried to instead write a flowing chapter that hopefully captures the interest of the reader.”
What was the hardest part of the work?
“As experimentalist, sometimes things are not behaving the way you expect. This is not fun, especially when time comes into consideration.”
… and the best part?
“The best part, of course, is when the work is appreciated – like being published in a journal, being referred to in other publications, or in general when people benefit from it.”
What piece of advice could you give to future doctoral students?
“Enjoy the doctoral process. It may be difficult, but at the end it is very rewarding. Absorb as many skills as you can, including writing an appealing piece of text.”
What are you up to now?
“I continue with my research in the same group."​

 
 

The Best Thesis Award at the Department of Physics  

The prize was founded in 2013 and is awarded annually to one or several doctoral students who have defended their thesis during that year. The awarded theses can serve as good examples for doctoral students in the early stages of their own thesis writing.
Besides the honor, the winner also gets a diploma and a monetary prize of SEK 10.000. The prize committee consists of researchers from every division within the department. 
The members of this year’s committee were Riccardo Catena, Paolo Vinai, Paul Erhart, Arkady Gonoskov, Marianne Liebi, Björn Agnarsson, Magnus Hörnqvist Colliander, Ermin Malic, Igor Zoric, and Timur Shegai. 

 

The prize committee about the awarded theses 2018:

“This year the committee has decided to share the prize between Sophie Viaene and Ferry Nugroho. They both did a great job and their theses are somewhat complementary - one theory, one experiment. However, both are related to light interacting with subwavelength objects, for photonics and material science applications, respectively. Sophie's thesis is exceptionally well written, there is a coherent flow of information throughout the whole work. Moreover, the thesis is very detailed, but at the same time very pedagogical, such that a person outside of the metamaterial field could follow and understand both basic and advanced concepts. Ferry's thesis has a fantastic introduction and motivation part. Also, here there was a great pedagogical and coherence aspect. Ferry is a great writer! Moreover, Ferry's work has generated a considerable cumulative impact due to the substantial amount of high-profile peer-reviewed publications on which the thesis is based (and also the work that was not included).  Altogether, this made us to choose Sophie and Ferry for the best PhD thesis award this time. The prize committee sincerely congratulates Sophie and her supervisor Philippe Tassin, as well as Ferry and his supervisor Christoph Langhammer with this achievement and wishes them success in the future.”
 

 
Text: Mia Halleröd Palmgren, mia.hallerodpalmgren@chalmers.se​
Photo of Ferry Nugroho: Helén Rosenfeldt
Photo of Sophie Viaene (at top): Mia Halleröd Palmgren
​​​

Published: Thu 14 Feb 2019.