People

Nicolas Grandjean received a PhD degree in Physics from the University of Nice – Sophia Antipolis in 1994 and shortly after joined the French National Center for Scientific Research (CNRS) as a permanent staff member. In 2004, he was appointed tenure-track Assistant Professor at the EPFL and promoted Full Professor in 2009. From 2012 to 2015 he was heading the Institute of Condensed Matter Physics. In 2016, he was visiting professor at the UCSB. He was awarded the Sandoz Family Foundation grant for Academic Promotion and received the “Nakamura Lecturer” Award in 2010 and the “Quantum Devices Award” at the 2017 Compound Semiconductor Week. His research interests are the physics and technology of III-V nitride semiconductors. CV available here

Marcia T. Portella Oberli received the PhD degree in 1987 from Université Pierre et Marie Curie, Paris, France, for a research work on coherent spectroscopy and diffusion of molecules in solution and in porous media. From 1989 to 1990, she was a post-doctoral fellow first at AT&T Bell laboratories and then at Lawrence Berkeley Laboratory, where her research was centered on ultrafast phenomena studies in semiconductors and in molecules, under the leadership of Dr. C. V. Shank. In 1991, she joined the group of W. Kaiser (Alexander von Humboldt Fellow) at Technical University of Munich, where she performed experimental studies of ultrafast processes on proton-transfer and on relaxation of hot holes in semiconductors. From 1994 to 1999, she was Maître-assistante at Université de Lausanne and her research was focused on real-time studies of electronic bubble formation in van der Waals solids. In late 1999, she joined the Laboratory of Quantum Optoelectronics at the Ecole Polytechnique Fédérale de Lausanne. Her research activity was mainly on studies of exciton and charged-exciton dynamics in semiconductor nanostructures. In 2008, she was appointed Maître d’Enseignement et de Recherche. Since then, her research activities have been focused on linear and nonlinear physics of confined polaritons in semiconductor microcavity. Since 2017, she has been a member of the Laboratory of Advanced Semiconductors for Photonics and Electronics. She is the author of more than 65 scientific articles published in peer-reviewed international journals (> 1100 citations). Since 2006, she has been teaching Optics in master classes in physics on nonlinear and pulsed optics, ultrashort pulse lasers, coherent and incoherent spectroscopy.

Raphaël Butté was born in Paris, France, in 1973. He received the PhD degree from the University Claude Bernard, Lyon, France, in 2000 for his research on the structural and optoelectronic properties of hydrogenated nanostructured silicon thin films with potential applications for photovoltaics and thin film transistors.

He then moved to the University of Sheffield (2000-2003), UK, to work as postdoctoral research associate in the group of Prof. Maurice S. Skolnick (Fellow of the Royal Society).

His research shifted to the optical properties of III-V semiconductors with a main focus on the nonlinear optical properties of cavity polaritons occurring in GaAs-based microcavities driven under resonant optical excitation.

In 2004, he moved to Ecole Polytechnique Fédérale de Lausanne (EPFL) as scientific collaborator in charge of optical spectroscopy at LASPE, a newly established laboratory directed by Prof. Nicolas Grandjean.

In 2010, he became permanent member of staff (Scientific Collaborator and Lecturer). He was promoted to the position of Senior Scientist in 2016.

His current research activity deals with planar waveguides, microdisks and photonic crystals made from III-nitride semiconductors. In particular, he is leading the activity focusing on: (i) the physics of exciton-polaritons in planar waveguides and (ii) high-β photonic crystal nanolasers.

He is the author of 104 scientific articles published in peer-reviewed international journals, 14 publications published in peer reviewed journals following an international conference (> 3500 citations, h-index: 30) and 6 book chapters.

He has given 28 invited talks in International Conferences/Winter-Summer Schools/Workshops.

He has been the Publications Chair/Guest Editor of the Proceedings of the 5th International Workshop on Nitride semiconductors (IWN2008) and also served as Scientific Secretary of IWN2008 and of the 5th International Conference on Spontaneous Coherence in Excitonic Systems (ICSCE5).

In 2012, he was one of the 149 scientists recognized by the Outstanding Referee program (http://publish.aps.org/OutstandingReferees) of the American Physical Society (APS) selected from a pool of roughly 60,000 currently active referees.

From September 2013 until December 2017, he was one of the Editors of the journal “Superlattices and Microstructures” (Elsevier).

Since September 2015 he is a member of the Physics Doctoral School Teaching Committee. He was also a member of the EPFL Teaching Conference from September 2015 until August 2017. CV available here

Gordon Callsen (G.C.) studied physics at “Technische Universität Berlin (TUB), Germany” and consequently was awarded with the “Wilhelm und Else Heraeus award“ of the “Physikalische Gesellschaft zu Berlin” in 2010 for outstanding study results. In 2015, G.C. received his PhD degree from University of Technology, Sydney (Australia) and TUB based on a cotutelle agreement (result: Summa cum laude). As a result, he was awarded with the “Carl-Ramsauer award” for his fundamental research on the optical properties of individual GaN quantum dots. In between 2012 and 2015 he was the scientific secretary of the CRC787 research project (DFG funding) with over 120 scientific members. In this function he significantly contributed to the extension of the project until 2019 based on his scientific (papers, proposal writing) and management (workshop and review meeting organisation) skills. After a one-year Postdoc period at TUB, G.C. moved to “École Polytechnique Fédérale de Lausanne (EPFL), Switzerland” in 2016 to research in the group of Prof. Dr. N. Grandjean (LASPE). Here, he continued his research on III-nitride based quantum dots and nanostructures, but also extended his scope to technologically most-relevant mixed crystal alloys. G.C. obtained a Marie-Skłodowska-Curie scholarship in 2017 (EU funding, “PhotoHeatEffect”, ID: 749565), aiming to pioneer the field of nano-thermometry based on III-nitrides. Generally, G.C.’s current research activities mostly deal with III-nitrides and II-oxides as the basis for advanced photonic and thermal characterization techniques relying on spectroscopy. Here, a special focus lies on time-resolved and correlation spectroscopy in the UV-DUV spectral range, aiming to study the interaction of one- and few-photon sources with the phonon bath. G.C. is authoring more than 50 scientific articles published in peer-reviewed journals (≈ 1000 citations, h-factor ≈ 20). The full CV is available here.

Sebastian Tamariz studied physics at the National Autonomous University of Mexico (UNAM). For his bachelor’s thesis he worked on Pulsed Laser Deposition (PLD) of Yttrium Iron Garnet (YIG) thin films. Afterwards he did a MSc in Material Science and Engineering also at the UNAM, where he worked on first principles simulations of amorphous III-V semiconductors. Currently he pursues his PhD studies in Photonics at EPFL, his work is focused on the fabrication of GaN quantum dots embedded on photonic crystals.

Camille Haller received her BSc and MSc degree in physics at EPFL in 2014. During the last year of her master, she did an internship in Alpes Lasers (Neuchâtel). She stayed in Alpes Lasers for her master thesis and worked on widely tunable quantum cascade lasers. From September 2014 to November 2015, she worked as a Junior Scientist in Alpes Lasers. She is currently pursuing a PhD in the Laboratory of Advanced Semiconductors for Photonics and Electronics (LASPE) at EPFL.

Thomas Weatherley received his BA and MSci degree in materials science at the University of Cambridge in 2018. For his master’s project he used photoconductive atomic force microscopy to analyse InGaN films. Currently he is pursuing his PhD in photonics at EPFL, with his research investigating the effect of alloy disorder on the properties of III-nitride heterostructures.

Yao Chen received her BSc and MEng degree in materials science and engineering at the Technical University of Madrid (UPM). During the last year of her master, she worked on the blue LEDs featured with GaN-based tunnel junction contacts for her master project at the Laboratory of advanced semiconductors for photonics and electronics (LASPE). Currently, she is pursuing her PhD in photonics at EPFL.