Bright people are always welcome to join our team!


nextnano team
Stefan Birner

Dr. Stefan Birner

Managing Director and

Stefan studied Physics at the universities of Bayreuth (Germany), Exeter (UK), Ohio State (USA) and the Technische Universität München (Germany).
During his studies, he gained experience through internships at companies such as Infineon Technologies and Genius CAD-Software.

Stefan holds a Master of Physics degree from the University of Exeter and a PhD in Physics from the Technische Universität München where he worked at the Walter Schottky Institute in the field of Theoretical Semiconductor Physics under the supervision of Prof. Peter Vogl.

In October 2012 he founded the nextnano GmbH where he serves as the managing director since November 2012.



stefan.birner [at]

Stefan Birner's profile on LinkedIn

Dr. Stefan Birner


Dr. Thomas Grange

Director of Research & Development

Thomas is Chairman and Research & Development Director of nextnano Lab SAS, an R&D company located in Grenoble, France.

Before founding nextnano Lab SAS, Thomas was working as Director of Research & Development at nextnano GmbH (2017-2021).

He is an expert on quantum cascade laser modeling using the non-equilibrium Green's function method.

Thomas was born in France and studied Physics at the École normale supérieure de Lyon (ENS Lyon) and at the École normale supérieure (ENS), Paris. He holds a bachelor (License) and a master (Maîtrise) degree in Physics from ENS Lyon and a Master in Quantum Physics degree from the ENS, as well as a PhD in Physics from Université Paris VI (Université Pierre-et-Marie-Curie). His PhD work was on the theory of electron-phonon interaction, polaron formation and dynamics in quantum dots in the group of Robson Ferreira and Gérald Bastard at the ENS. During his studies, he spent a few months with Danny Segal at the Imperial College London (UK) and with Lu J. Sham at the University of California, San Diego (USA).

Before joining nextnano in 2017, he worked for 8 years as a Postdoc. Half of this time he spent with a Humboldt Research Fellowship at the Walter Schottky Institute of the Technische Universität München (Germany) in the group of Peter Vogl on the modeling of quantum cascade lasers. At the Institut Néel (CNRS) in Grenoble (France) he was working in the Nanophysics and Semiconductors group of Alexia Auffèves on modeling of quantum dots and nitrogen-vacancy centers in diamond.



thomas.grange [at]

Thomas Grange's profile on LinkedIn


Dr. Alex Trellakis

Research & Development

Alex was born in the Netherlands and has a profound knowledge in both Physics and Computer Science. He holds a master (Diplom) degree in Physics from Friedrich-Wilhelms Universität Bonn (Germany), and both a Master of Science in Physics and a Master of Computer Science degree from the University of Illinois at Urbana-Champaign (USA), as well as a PhD in Physics from the University of Illinois at Urbana-Champaign (USA). During his PhD he investigated computational approaches to silicon-based nanostructures in the group of Prof. Umberto Ravaioli.

After his graduation, Alex worked 1 year as Research Scientist at Science Applications International Corporation (now Leidos) (USA) and 2 years as Senior TCAD Engineer at Intel Corporation (USA). Then, from 2002 to 2006, he worked as assistant professor at the Walter Schottky Institute of the Technische Universität München (Germany) in the group of Prof. Peter Vogl where he developed the nextnano++ software. Afterwards, Alex has been working for many years as software architect for DrVis Software GmbH and as technical consultant in a patent law firm.

At nextnano, Alex is our expert on device physics, numerical methods and software engineering.


alex.trellakis [at]


Maria Cecilia da Silva Figueira

Research & Development and Customer Support

Maria was born in São Paulo, Brazil and holds a BSc degree in Physics, a MSc degree in Nuclear Physics and an Electrical Engineering degree, all from the Universidade de São Paulo, Brazil. Before joining nextnano she worked as a Digital Integrated Circuit Design Engineer for the Ministry of Science, Technology and Innovation of Brazil. At nextnano she is leading our LED, laser diode and nanotransistor modeling business and makes our users happy by answering their support questions.



maria.figueira [at]

Maria Cecilia da Silva Figueira's profile on LinkedIn


Carola Burkl

Software Development

Carola holds a BSc degree in Engineering Physics and a MSc degree in Micro- and Nanotechnology, both from the Hochschule München. During her Bachelor thesis “Optimization of Terahertz Quantum Cascade Lasers – Numerical analysis of the Influence of Material Parameters on the Gain” she was using the nonequilibrium Green's function approach to simulate quantum transport in QCLs. In her Master thesis she was working at the company Blickfeld on the experimental characterization of MEMS mirrors that are used in Lidar systems.

In 2012 she founded the school “Ecole Assokoto des Sourds” in Togo. If you want to support these activities, you can also contribute with a donation.

At nextnano, Carola is responsible for the nextnanomat graphical user interface.


carola.burkl [at]

Carola Burkl's profile on LinkedIn


Takuma Sato

Research & Development

Takuma was born in Aichi, Japan and holds BSc (2018) and MSc (2021) degrees in Physics from Tohoku University in Sendai, Japan. He studied theoretically the magnetoelastic coupling and spintronics in insulators under the supervision of Prof. Gerrit E. W. Bauer in the Condensed Matter Theory group at the Institute for Materials Research (IMR) of Tohoku University.

In 2019-2020, he worked in our R&D team as an intern via the 1-year program “Vulcanus in Europe” of the EU-Japan Centre for Industrial Cooperation and developed the nextnano++ tutorials on laser diodes, wurtzite piezoelectricity, solar cells and optical absorption. From May 2021, he engages in developing the nextnano.NEGF software for Interband Cascade Lasers within the EU Innovative Training Network QUANTIMONY (PhD programme). He is enrolled as a PhD student in Electrical Engineering at the Technische Universität München.



takuma.sato [at]

Takuma Sato's profile on LinkedIn


Dr. Herbert S. Mączko

Research & Development

Herbert was born in Poland and studied at Wroclaw University of Science and Technology (WUST) in Wroclaw. He holds degrees of Bachelor of Engineering and MSc in Technical Physics with a specialisation in Nanoengineering, as well a degree of Doctor of Sciences in Physical Sciences. His doctoral work, under the supervision of Prof. Marta Gładysiewicz, was focused on calculations of electronic band structures and optical gain spectra of GeSn- and BGaAs-based quantum wells (QWs) for integration with Si platform. Before joining nextnano in 2022, he worked as an Assistant Professor in the group of Prof. Robert Kudrawiec at WUST, where he got involved in spectroscopy measurements and characterisation of: GeSn alloys, BGaInAs-based QWs, and GaInAsSb-based Digital Alloys. At nextnano, Herbert is supporting the team with his programming skills and experience in semiconductor materials, along with helping our users to be fully satisfied with the nextnano software.



herbert.maczko [at]

Herbert S. Maczko's profile on LinkedIn


Heorhii Yehiazarian

Research & Development

Heorhii was born in Ukraine. He holds a BSc degree in Applied Physics and Energy Systems from the National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute” in Kyiv, Ukraine. He also holds a MSc degree in Material Science (Erasmus Mundus programme of Université de Rennes, Technische Universität München and Ludwig-Maximilians-Universität München).

At nextnano, he is working on R&D, focusing on the modeling of germanium-silicon Quantum-Confined-Stark-Effect electro-absorption modulators (EAM) within our EU project SiPHO-G and on the nextnanopy Python package.


heorhii.yehiazarian [at]

Heorhii Yehiazarian's profile on LinkedIn


Dr. Oleg Yevtushenko

Research & Development

Oleg was born in Kharkov, Ukraine. He holds a Master of Science Diploma in Solid State Physics from Kharkov Polytechnic University, Kharkov, Ukraine and a PhD in Solid State Physics from Institute of Radiophysics and Electronics, National Academy of Sciences of Ukraine (IRE NASU), Kharkov. His scientific career path included positions at

  • Institute for Theoretical Condensed Matter Physics, Karlsruhe Institute of Technology (KIT), Germany
  • Institute of Radiophysics and Electronics, National Academy of Sciences of Ukraine (IRE NASU), Kharkov, Ukraine
  • Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
  • University of Regensburg, Regensburg, Germany
  • Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy
  • Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany
  • Ludwig-Maximilians-Universität München, Munich, Germany.
His research activities are in the areas of
  • Symmetry protected transport in topological insulators and quantum wires
  • Low-dimensional systems with interactions
  • Transport and quantum phenomena in mesoscopic systems and carbon nanotubes
  • Localization transition and criticality in disordered systems
  • Unconventional random matrix theories and their application in physics
  • Transport and rectification in classically chaotic systems.

At nextnano he is working on advanced research topics such as Electron Flying Qubits.


oleg.yevtushenko [at]


Niklas Pichel

Research & Development

Niklas was born in Germany. He is currently studying Engineering Physics (BSc) at the University of Applied Sciences Munich. His interests are mainly in optics, micro- & nanotechnology and numerical modeling. At nextnano he is interning for five months.


niklas.pichel [at]


Jörg Stratmann

Software Development

Jörg holds a Diplom degree in Computer Science from the University of Bonn, Germany.
During his diploma thesis at the University of Bonn he was working on robotics and artificial intelligence. Since 1999 he has been working as a software developer for a German television channel.

He works as a part-time employee for nextnano and as our cloud computing expert he is responsible for the integration of HTCondor, Azure and aws into our graphical user interface.


joerg.stratmann [at]


Lucie Marion Leguay

Research & Development

Lucie was born in Le Mans, France. She holds a BSc degree in Physics from the University of Rennes 1, France and a MSc degree in Fundamental Physics from the University Claude Bernard Lyon 1, France. In her Master’s degree, she specialized in atomic and molecular physics, condensed matter systems and optics and did a four-month research internship at the Quantum Photonics, Electronics and Engineering Laboratory (PHELIQS) at CEA Grenoble. In November 2021, she joined the Institute of Solid State Physics of the Technische Universität Berlin, Germany to pursue her PhD under the supervision of Andrei Schliwa. She takes part in the EU project QUANTIMONY, funded by the Marie Skłodowska-Curie Actions and focuses her research on inverse design numerical methods for III-Sb devices. As a secondment within the QUANTIMONY project, she spent one month at nextnano during summer 2022.


lucie.leguay [at]

Lucie Marion Leguay's profile on LinkedIn


Zhi Rong Tan

Business Development and Sales Specialist

Zhi Rong was born and raised in Singapore, where he is pursuing a BEng degree in Civil Engineering and a MSc degree in Finance at the National University of Singapore. Leading up to his time at nextnano, he spent three years as a financial analyst and copywriter for Dr Wealth, a Singapore start-up. During his stint at nextnano, he will be completing an internship here through the NUS Overseas College entrepreneurial programme.


zhirong.tan [at]

Zhi Rong Tan's profile on LinkedIn