Welcome to the MultioptiX Group

April 2024

M. Schmid's, M. Ketharan's, J. Lucaßen's and I. Kardosh's paper has been published in the journal Advanced Materials Interfaces. Sequentially PVD-Grown Indium and Gallium Selenides Under Compositional and Layer Thickness Variation: Preparation, Structural and Optical Characterization“10.1002/admi.202301086 (author version) (supp.info)

Congratulations to all of you!

March 2024

Yao Gao's and Christop Rath's (first authors) paper has been published in the journal Advanced Materials Interfaces. Impact of Band-gap Gradient in Semi-Transparent and Bifacial Ultra-Thin Cu(In,Ga)Se2 Solar Cells“10.1002/adom.202300697 (author version) (supp.info)


December 2023

Our bachelor students Niklas Fröse and Elias Hänel have successfully completed their bachelor theses.

Niklas: Untersuchung der Ladungsträgerlebensdauer in Chalkopyritschichten und -solarzellen mittels zeitaufgelöster Photolumineszenz und Kapazitäts-Spannungs Messungen. (thesis on request)

Elias: Laserprozessierung zur Herstellung von Masken für Solarzellen. (thesis on request)

Congratulations, Niklas and Elias!

October 2023

Martina Schmid's paper has been published in the journal Advanced Optical Materials. Revisiting the Definition of Solar Cell Generations“10.1002/adom.202300697 (author version)

September 2023

From 18 - 22 September Tristan Köhler, Jan Lucaßen and Martina Schmid joined the 40th European Photovoltaic Solar Energy Conference (EU PVSEC) in Lisbon with 3 poster presentations. The EU PVSEC is the largest specialised  PV conference  and the best way to discuss research topics and expand your knowledge in PV. The next EU PVSEC will take place from 23 - 27 Sept 2024 in Vienna, Austria.

September 2023

In the same month, Yao Gao's paper has been published in the journal Advanced Materials Interfaces. Rear Interface Engineering in Solution-Processed Submicron Cu(In,Ga)(S,Se)2 Solar Cells on Transparent Sn:In2O3 Back Contact“10.1002/admi.202300566 (author version)

August 2023

We would like to welcome our new bachelor student Elias Hänel. He will join our group until December 2023. Welcome Elias!

August 2023

Christoph Rath has successfully completed his bachelor thesis on Tuning Ga-gradient and Na concentration in Cu(In,Ga)Se2 solar cells“. Congratulations, Christoph! (thesis on request)

June 2023

Yao Gao's paper has been published in the journal Small. Sodium Incorporation for Performance Improvement of Solution-Processed Submicron CuIn(S,Se)2 Thin Film Solar Cells“10.1002/smll.202302581 (author version) (supp.info.)

June 2023

On Monday 5th June we made an excursion to the Baldeneysee in Essen with the MultioptiX group. The weather was fantastic so that we had a great time on our canoeing tour there. After the 3 hour tour we spent some time at the sea side beach, had lunch and ice cream before we head back home.

April 2023

We would like to welcome our new students Camillo Hinz (master) and Christoph Rath (bachelor) in our group. In May Niklas Fröse (bachelor) and Mithuran Ketharan (bachelor) will join the group as bachelor students as well. We look forward to working with them!

March 2023

Samuel Kidane has successfully completed his bachelor thesis on Herstellung und Charakterisierung von Mikrolinsen für Mikrokonzentratorsolarzellen. (thesis on request)

January 2023

Julius Kruip's paper has been published in the journal Processes. Growth of (Ag,Cu)(In,Ga)Se2 Absorbers under Band Gap Variation and Characterization with a Focus on Optical Spectroscopyhttps://doi.org/10.3390/pr11020392 (author version) (supp.info.)

December 2022

Jan Lucassen's and Setareh Sedagaht's paper has been published.

"Realistic Multidimensional Optoelectrical Modeling Guide for Copper Indium Gallium Diselenide Solar Cells"

https://doi.org/10.1002/solr.202200867 (author version) (supp.info.)

Heidi Paerschke

​December 2022

Our lovely colleague Heidi Pärschke went into her well-deserved retirement. A great thanks to her support and her loyalty for the MultioptiX team. Before she worked for Prof. Schmid, she already had been working for Prof. Buck and Prof. Mergel for many years. T. Huong Witte-Nguy who is the new assistant of the group will do her best to fill the big gap she left behind.

November 2022

Julius Kruip  has successfully completed his master thesis on “Growth of (Ag,Cu)(In,Ga)Se2 - Absorbers under Band Gap Variation and Characterization with a focus on Raman-Spectroscopy“.

September 2022

Yao Gao's publication has been accepted.

"8.0% Efficient Submicron CuIn(S,Se)2 Solar Cells on Sn:In2O3 Back Contact via a Facile Solution Process"

https://doi.org/10.1021/acsaem.2c01764 (author version) (supp.info.)

September 2022

Yong Li's publication has been accepted.

"Beyond Light-Trapping Benefits: The Effect of SiO2 Nanoparticles in Bifacial Semitransparent Ultrathin Cu(In,Ga)Se2 Solar Cells"

https://doi.org/10.1002/solr.202200695 (author version)

Dipl. Phys. Ing. Klaus Pärschke

​August 2022

Our dear friend and colleague Klaus Pärschke went into his well-deserved retirement. We thank him very much for the many years he supported the team with his unique technical expertise. Ihab Kardosh and Tristan Köhler try to fill the big gap he left behind.

Editorial on the Research Topic

Advanced opto-electrical modeling of photovoltaic materials and devices

Janez Krc1*, Martina Schmid and Rudi Santbergen

in Frontiers in Photonics


DOI 10.3389/fphot.2022.977946, (open access)

Logo die kleine Form

​June 2022

Prof. Dr. Martina Schmid gave a lecture in German on the topic: "Elektrizität von der Sonne – mit Solarzellen der nächsten Generation" as part of the "DIE KLEINE FORM" series of events.
DIE KLEINE FORM offers a pointed and also entertaining insight into the questions and methods of the disciplines taught at the University of Duisburg-Essen.

The recorded lecture can be accessed here: https://www.uni-due.de/kleine-form/schmid.php

June 2022

Yong Li's publication has been accepted.

"Ultrathin Cu(In,Ga)Se2 Solar Cells with a Passivated Back Interface: A Comparative Study between Mo and In2O3:Sn Back Contacts"

https://doi.org/10.1021/acsaem.2c00088  (author version) (author version supp. inform.)

June 2022

New virtual lab tour videos were published:

Virtual lab tours

Get a unique sneak peek into our research laboratories and characterization methods!

January 2022

Yong Li's publication has been accepted.

"Bifacial semi-transparent ultra-thin Cu(In,Ga)Se2 solar cells on ITO substrate: How ITO thickness and Na doping influence the performance"


October 2021

Julius Kruip has successfully completed his bachelor thesis on “Bifaziale und winkelabhängige elektrische Charakterisierung von semitransparenten CIGSe-Ultradünnschicht-Solarzellen ohne und mit Nanopartikeln“.

August 2021

Camillo Hinz has successfully completed his bachelor thesis on “Die optische Charakterisierung von semitransparenten Solarzellen mit integrierten Nanostrukturen“. (thesis on request)

July 2021

Summer semester 2021

End of lectures

January 2021

Yong Li's publication has been accepted.

"Sodium control in Ultrathin Cu(In,Ga)Se2 solar cells on transparent back contact for efficiencies beyond 12%"


February 2020

Jan Lucaßen  has successfully completed his master thesis on “Implementation of a CV-Measurement and Analysis Routine for Solar Cells“.

August 2019

Lukas Schneider has successfully completed his bachelor thesis on “Inkjet printing of CIGSe absorber islands“.

July 2019

Erika Gutiérrez has successfully completed her 2-month internship on the topic “Fabrication and characterization of AIGS absorber layer”

Februar 2019

Henrik Mantke has successfully completed his master thesis on “Untersuchung der Veränderung der Passivierungseigenschaften von amorphem Silizium-Suboxid-Schichten durch Indiumzinnoxid-Sputtern“.

Februar 2019

Jan Dippell has successfully completed his master thesis on “ Light-splitting concept for residential solar applications“.

Januar 2019

Jan Lucaßen has successfully completed his bachelor thesis on “Mechanische Substratstrukturierung für lokale Indiumabscheidung“.

September 2018

Florian Beineke has successfully completed his master thesis on “Direkte, winkelabhängige und integrale VIS/NIR-Spektroskopie zur Charakterisierung von Solarzellenschichten“.


Porträt von Frau Prof. Dr. Martina Schmid
Prof. Dr. Martina Schmid, Foto: UDE/Frank Preuß

MultioptiX Prof. Dr. Martina Schmid assumes the professorship of experimental physics at the University of Duisburg-Essen

On 1 January 2017, Martina Schmid assumed the W2 professorship of “experimental physics” in the Physics department of the University of Duisburg Essen. From 2012 to the end of 2016, Martina Schmid headed the Helmholtz Young Investigator Group “Nano-Optical Concepts for Photovoltaics” at HZB.

Antrittsvorlesung 19: April 2017

"I look forward to my new function at the University of Duisburg-Essen because it gives me the opportunity to continue pursuing my research topics in the field of solar energy and to develop new ideas," Martina Schmid says about her new appointment at the University of Duisburg-Essen.

Before her move, Martina Schmid and her team at HZB researched into nano-optical concepts for chalcopyrite solar cells. These solar cells already achieve high efficiencies, but require rare and expensive materials to produce. The young investigator group’s aim was therefore to minimise the usage of rare elements in chalcopyrite solar cells while maintaining or even increasing their efficiency.

"By integrating nanostructures into ultra-thin CIGSe solar cells, we successfully demonstrated a significant increase in the short-circuit current density. In cooperation with the Institute for Atomic and Molecular Physics (AMOLF) in the Netherlands, we were able to achieve up to 93 percent of the maximum value attained by a thick CIGSe solar cell," Martina Schmid reports. The short-circuit current is the maximum current that a solar cell or photovoltaic module can deliver.

In a project with the Federal Institute for Materials Research and Testing (BAM) and the Leibniz Institute for Crystal Growth (IKZ), Martina Schmid’s HZB young investigator group also succeeded in producing CISe absorbers that considerably reduce the usage of rare elements. Papers were published for both results in which the EE-NOPT group was involved.

Martina Schmid will continue to supervise the members of her former young investigator group until they have finished their final theses; they have since been integrated into various organisational units at HZB.