Dr. Olaf Hohm comes to the HU with an ERC-Grant

The Mathematical Physicist Olaf Hohm, who acquired an ERC Consolidator Grant for his research project "Duality Symmetries, Higher Derivatives and their Applications in Cosmology", has moved to the Department of Physics at Humboldt-Universität zu Berlin. Previously, he received a "Heisenberg scholarship from the DFG and worked at MIT in Boston and at Stony Brook University in New York. His current research interest is the development of a string-theoretical approach to answer questions about the beginning of the universe purely arithmetically. He will work closely with the IRIS member groups Prof. Jan Plefka and Prof. Matthias Staudacher. Dr. Hohm presents his research at 26.10.2018, 1:15 pm in the IRIS-building, room 2'07.

IRIS Adlershof is looking forward to a fruitful cooperation!


Dr. David Bléger joins CREAVIS, the strategic innovation unit of EVONIK

IRIS junior research group leader David Bléger joins CREAVIS, the strategic innovation unit of EVONIK. After studying and working in France, he joined IRIS member Stefan Hecht as a postdoc in 2009 and started his own working group in 2013. He is an expert in the design and manufacture of molecules, polymers and various organic materials that respond to chemical and physical stimuli.

IRIS Adlershof wishes you lots of success!


Egon Steeg successfully defended his dissertation

IRIS Junior Scientist Egon Steeg successfully defended his dissertation "Investigations on growth and structure of silver and silver halide nanostructures formed on amphiphilic dye aggregates". His research was supported by CRC 951 "Hybrid Inorganic/Organic Systems for Opto-Electronics (HIOS)" and supervised by PD Dr. Stefan Kirstein in the group of  IRIS-Director Prof. Jürgen P. Rabe.

IRIS Adlershof congratulates!


Printing solar cells and organic LEDs - HZB & HU cooperate

Humboldt-Universität zu Berlin and Helmholtz-Zentrum Berlin form a joint lab and research group “Generative production processes for hybrid components”.
Solar cells, LEDs and detectors made of organic and hybrid semiconductors can nowadays be simply printed out, even together with teensy nanostructures that make them function better. The development of low-cost printing methods for electronic and optoelectronic components is at the centre of things for the new joint research group and the joint laboratory of the Helmholtz-Zentrum Berlin (HZB) and Humboldt-Universität zu Berlin (HU).

  The HySPRINT logo (Helmholtz Innovation Lab) printed on a copper solution symbolizes how the thinnest material layers can be produced simply and cost-effectively. Possible applications are solar cells, organic LEDs or transistors.
Photo credit: Humboldt Universität zu Berlin/List-Kratochvil


Cooperating together in the new research group are the HU workgroup “Hybrid Devices” led by Prof. Dr. Emil List-Kratochvil, the HZB young investigator group of Dr. Eva Unger, the Helmholtz Innovation Lab HySPRINT, and the Competence Centre Photovoltaics Berlin (PVcomB) directed by Prof. Dr. Rutger Schlatmann. The partners are building up a joint lab at Humboldt-Universität zu Berlin that will allow the researchers to acquire and use complementary laboratory infrastructures for various coating methods.
Prof. Emil List-Kratochvil is the head of the HU workgroup “Hybrid Devices” at IRIS Adlershof, and has been working for 15 years on developing electronic and optoelectronic hybrid components, resource-efficient deposition techniques (inkjet printing) and in-situ nanostructuring and synthetic methods. This expertise complements the aims of the HZB young investigator group led by Dr. Eva Unger. She will be developing solution-based manufacturing methods for depositing perovskite semiconductor layers onto larger surface areas for solar cells. “The new research group with List-Kratochvil is a real win for us. With his experience in printed electronic components, he is an ideal cooperation partner for us,” Unger says.
In recent months, the researcher and her team have already come much closer to her goal of developing hybrid tandem solar cells with large-surface-areas in the scope of the Helmholtz Innovation Lab HySPRINT. Now, the next step is to upscale the process in order to drive the novel solar cells towards market maturity. The Competence Centre Thin-Film- and Nanotechnology for Photovoltaics Berlin (PVcomB) is the ideal partner for the development of industrially relevant manufacturing processes. The joint research group is now striving towards building a pilot line on which to develop prototypes of hybrid components.



Michael N. Borinsky’s dissertation will be released by Springer Theses

The dissertation of Dr. Michael N. Borinsky was selected to be published in Springer Theses, a dedicated book series to recognize outstanding doctoral research and received an reasearch award worth 500 €. Borinsky was IRIS Junior Scientist and supervised by  IRIS-Member Prof. Dirk Kreimer.
"This thesis provides an extension of the work of Dirk Kreimer and Alain Connes on the Hopf algebra structure of Feynman graphs and renormalization to general graphs. Additionally, an algebraic structure of the asymptotics of formal power series with factorial growth, which is compatible with the Hopf algebraic structure, will be introduced. [...] [Part of these] structures are motivated by and used to analyze renormalized zero-dimensional quantum field theory at high orders in perturbation theory. As a pure application of the Hopf algebra structure, an Hopf algebraic interpretation of the Legendre transformation in quantum field theory is given."

IRIS Adlershof would like to congratulate Michael Borinsky and wishes him much success in his future work.1

Dr. Michael Norbert Borinsky
Graphs in Perturbation Theory: Algebraic Structure and Asymptotics
Springer Theses, Springer (angekündigt)
PhD thesis "Graphs in perturbation theory: Algebraic structure and asymptotics"
DOI: 10.18452/19201, arXiv: arXiv:1807.02046 [hep-th], 1edoc-HU: 18452/19952



Flipping the switch on supramolecular electronics

For the first time, two-dimensional materials have been decorated with a photoswitchable molecular layer, and electronic components have been fabricated from the resulting hybrid materials that can be controlled by light. The results of this fruitful collaboration of several European research groups have been published in Nature Communications.

Owing to their outstanding electrical, optical, chemical and thermal properties, two-dimensional (2D) materials, which consist of a single layer of atoms, hold great potential for technological applications such as electronic devices, sensors, catalysts, energy conversion and storage devices, among others. Thanks to their ultra-high surface sensitivity, 2D materials represent an ideal platform to study the interplay between nanoscale molecular assembly on surfaces and macroscopic electrical transport in devices.

In order to provide a unique light-responsivity to devices, the researchers have designed and synthesized a photoswitchable spiropyran building block, which is equipped with an anchoring group and which can be reversibly interconverted between two different forms by illumination with ultraviolet and visible light, respectively. On the surface of 2D materials, such as graphene or molybdenum disulfide (MoS2), the molecular photoswitches self-assemble into highly ordered ultrathin layers, thereby generating a hybrid, atomically precise superlattice. Upon illumination the system undergoes a collective structural rearrangement, which could be directly visualized and monitored with sub-nanometer resolution by scanning tunneling microscopy. This light-induced reorganization at the molecular level induces an optical modulation of the energetics of the underlying 2D material, which translates into a change in the electrical characteristics of the fabricated hybrid devices. In this regard, the collective nature of self-assembly allows to convert single-molecule events into a spatially homogeneous switching action, which generates a macroscopic electrical response in graphene and MoS2.

"With our versatile approach of molecularly tailoring 2D materials, we are taking supramolecular electronics to a new level and closer to future applications," says Prof. Stefan Hecht, who is researching hybrid materials at IRIS Adlershof. The work is groundbreaking for the realization of multifunctional hybrid components powered by nature's primary energy source - sunlight.

Further Information


“Collective molecular switching in hybrid superlattices for light-modulated two-dimensional electronics”

by: Marco Gobbi, Sara Bonacchi, Jian X. Lian, Alexandre Vercouter, Simone Bertolazzi, Björn Zyska, Melanie Timpel, Roberta Tatti, Yoann Olivier, Stefan Hecht, Marco V. Nardi, David Beljonne, Emanuele Orgiu and Paolo Samorì

in: Nature Communications 2018, 9, 2661, DOI: 10.1038/s41467-018-04932-z