Well-deserved award for outstanding research at Helmut Schmidt University/University of the Federal Armed Forces Hamburg (HSU/UniBw H): At the NATO Research Symposium on “Detection, Tracking, ID and Defeat of Small UAVs in Complex Environments” in Copenhagen, five scientists from the Chair of Electrical Measurement Technology now received the NATO Best Paper Award. Alexander Wentzel accepted the award on behalf of all five authors – Prof. Dr. Gerd Scholl, Dr.–Ing. Ralf Heynicke, Jan Cornils, Marco Valentin and himself. Topic of the paper: “Compact Counter-UAS System for defeating small UAV in Complex Environments”.

Congratulations!

Scientists from Hamburg^[1] and Munich^[2][3] developed  the world’s most powerful dual-comb spectrometer that paves the way for many applications in atmospheric science and biomedical diagnostics, such as early cancer detection.

Two trains of laser pulses with slightly different spacing originate from a thin-disk laser gain medium in the center of the picture. The work was recently published in Nature Communications. © Eric Schambroom, Patricia Bondia. Image usage only for reporting on this press release.

The core part of the system is a special type of laser-gain medium, a thin-disk, and a unique configuration of the mirrors surrounding this medium, a laser resonator (shown in the illustration). “The key of our dual comb laser source lies in its simplicity”, team leader Oleg Pronin explains. “Instead of using two separate lasers, actively stabilizing and locking them to each other, our two laser outputs originate from the same laser resonator, leading to an excellent intrinsic mutual stability.” The dual-output laser yields one order of magnitude higher power than ever before. This paves the way for many applications in atmospheric science and biomedical diagnostics, such as early cancer detection. Fundamental research applications such as precise measurements of the atomic lines in uncovered spectral ranges and nuclear clocks, the most precise clocks in our universe, come into reach thanks to this novel spectrometer. 

The dual-comb spectrometer converts extremely fast electric field oscillations (10¹⁵ oscillations per second) of light into radiofrequency range (10⁶ oscillations per second), where the signal can be detected in real-time with modern electronics. The process is realized with two trains of laser pulses with slightly different spacing. It offers high sensitivity and resolution with fast acquisition times in the millisecond time scale. Megawatt level peak powers pave the way toward high-resolution spectroscopy in the deep ultraviolet frequency range via frequency conversion – a spectral domain yet poorly covered in today’s spectrometers. Compared to complex, actively stabilized laser systems, the compact size facilitates real-world applications, such as atmospheric sensing and high-precision distance measurements.

This article refers to the following publication in Nature Communications :

“Fritsch, K., Hofer, T., Brons, J. et al. Dual-comb thin-disk oscillator. Nat Commun 13, 2584 (2022). https://doi.org/10.1038/s41467-022-30078-0”

For more details please contact:

Prof. Dr. Oleg Pronin

Fakultät für Elektrotechnik, Helmut Schmidt Universität Hamburg

[email protected]

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^[1] Helmut Schmidt University, Hamburg, Chair of Laser Technology & Spectroscopy; www.hsu-hh.de/lts

^[2] Max Planck Institute of  Quantum Optics, Munich; www.mpq.mpg.de

^[3]Attoworld-Team around Prof. Ferenc Krausz at Ludwig-Maximilians Universität (LMU), Munich; www.attoworld.de 

Detlef Kip is professor for Experimental Physics and Material Sciences.

In coordination with several industrial partners, he is researching non-linear optical materials in the LINOBUS project. Non-linear optics or optically non-linear materials are used, among other things, in the construction of optical switches and modulators. For example, green laser pointers often contain diodes that generate infrared light, which is frequency-doubled by a nonlinear crystal and thus turns green. They can also be used as components in optical data and image processing.

Non-linear optical materials make it possible, especially at high light intensities, to specifically change the wavelength (light colour) of irradiated light. Examples of such processes are frequency doubling (halving the wavelength, for example from red to blue) or, conversely, optical parametric generation. Here, for example, a blue light particle “decays” into two red light particles, which are then in an “entangled” state as a photon pair. In entanglement, two particles that were formerly generated as a pair are connected in their properties even after their spatial separation. Together with the use of semiconductor lasers as pump light sources and optical waveguides, these materials make it possible in principle to create new compact and inexpensive light sources for a wide range of applications in photonics and quantum technologies.

In order to bring new efficient light sources for the near ultraviolet spectral range in particular further into application, the LINOBUS project funded by the German Federal Ministry of Education and Research (BMBF) is to research and specifically improve the material properties and technological principles of periodically poled lithium tantalate waveguides. LINOBUS stands for “Lithium tantalate waveguides for non-linear optics in the blue and ultraviolet spectral range at high powers”. The concrete aim is to produce so-called rib waveguides by a novel process (diamond sawing) and to make them less sensitive to high light powers by introducing certain types of atoms. Further work concerns the development of processes that are also suitable for mass production for the generation of periodically poled crystals, which are necessary for particularly efficient light conversion. Especially the generation of very small periods in the crystal, as they are required in the ultraviolet spectral range, pose a challenge.

“If the work delivers the hoped-for results, materials and processes will be available for the realisation of new types of compact beam sources that will enable a wide range of applications, for example for highly efficient photon sources, for quantum metrology or fluorescence spectroscopy in medical applications, for example,” explains project coordinator Univ.-Prof. Dr. Detlef Kip (Professur für Professur für Experimentalphysik und Materialwissenschaften).

Additonal information

https://www.hsu-hh.de/laser/forschung
https://www.quantentechnologien.de/forschung/foerderung/wissenschaftliche-vorprojekte-wivopro-photonik-und-quantentechnologien/linobus.html

Scientific contact

Univ.-Prof. Dr. habil. Detlef Kip, Tel. 040 6541-2457, E-Mail [email protected]

Original taken from this page

Helmut Schmidt University received top ratings in several subjects in the current CHE university ranking, which was published 3. Mai 2022 in the new ZEIT study guide. In particular, support at the beginning of studies received top marks.

Top in support at the beginning of studies: In these categories, the fields of civil engineering, electrical engineering and information technology, and mechanical engineering reached the top group in the ranking published today by the Center for Higher Education Development (CHE).

Top marks from the students were also awarded for the Library equipment in the specialties Electrical engineering and information technology, Education and educational science as well as Psychology.

Students in the Faculty of Electrical Engineering also gave the laboratory equipment a grade of 1.5. Students in the Faculty of Humanities and Social Sciences particularly liked the way their studies were organized: in the fields of Education and Educational Science and Psychology, there were top ratings for this (1.7 and 1.3, respectively).

“I am pleased that we were able to maintain the good ratings of previous years despite the pandemic restrictions. I am particularly pleased with the very positive student evaluations. They show that our teachers have done a lot right in the forced conversion to hybrid or digital teaching,” said HSU President Prof. Dr. Klaus Beckmann.

The CHE University Ranking is considered to be a particularly comprehensive and detailed ranking in the German-speaking world. In addition to studies, teaching, facilities and research, the ranking also includes students’ assessments of the study conditions at their university. Each subject is re-evaluated every three years. This year, subjects in engineering, linguistics, cultural studies and psychology were examined. For the first time, students were also asked about the use of digital teaching.

The CHE-Ranking in Internet: www.zeit.de/che-ranking

The Professorships for Electrical Energy Systems (Prof. Dr.–Ing. Detlef Schulz) and Werkstofftechnik (Prof. Dr.–Ing. Thomas Klassen) of Helmut Schmidt University Hamburg, together with Altran Deutschland S.A.S. & Co. KG have raised around six million euros in research funding for hydrogen research at the Hamburg site. “HyReflexS” deals with hydrogen-based emergency power supply with integrated control power plant by means of flexible sector coupling and metal hydride storage.

In the interdisciplinary research project “HyReflexS”, funded by the German Federal Ministry for Economic Affairs and Energy (BMWi), the use of modern hydrogen technologies in sector coupling is being researched at the HSU. The industrial partners involved are Altran Deutschland S.A.S. & Co. KG as direct partners and Stromnetz Hamburg GmbH, Gasnetz Hamburg GmbH and Hamburger Hochbahn AG as associated partners. Within the framework of the project, which has a duration of 3 years, novel switchable systems based on PEM fuel cells and electrolysers will be developed and used for the coupling of the electricity and gas sectors. For this purpose, a virtual integration into the control systems of the research partners will be carried out for the first time. This will be complemented by research into innovative metal hydride storage systems and compressors, which will enable an additional increase in efficiency through heat coupling. The goal of the project is a demonstrator for a redesign of emergency power systems of large electric consumers, such as depots of electric buses. The novel approach results in multiple potentials for load curve smoothing, peak load reduction and more efficient use of renewable generators. In addition, the coupling of the electricity and gas sectors enables an increase in supply security and capacity, which also opens up new economic potential.

Note: Within the framework of the HyReflexS project, the professorships Schulz [here] and Klassen [here] are still searching for personnel reinforcement.

With an outstanding thesis, Yasmin Kopp completed her master’s degree in physics at the University of Hamburg in December 2021 with a focus on laser physics and photonics. Since January 2022, she has been a doctoral student at the Chair of Laser Technology and Spectroscopy. There, the physicist is working on her dissertation on “Table-top source of extreme ultraviolet frequency combs for precision metrology applications.” She is supported for three years by the Hamburg Career Competence Center for Women’s, Pro Exzellenzia, promoted.

After graduating from high school, she studied physics in Münster and completed her bachelor’s degree in Glasgow, Scotland. She came to the University of Hamburg in 2019 to study for her master’s degree. At the same time, she also became a student assistant at the Professorship for Laser Technology and Spectroscopy of the Helmut-Schmidt-University.

Now the physicist is involved on a daily basis with basic research for the development of new laser technologies. “Simply put, it involves spectroscopic and metrological applications, such as the spectroscopy of thorium for the future generation of ultraprecision clocks. I stand in the lab all day and build optical devices myself.”

For most of her school years, she was not interested in mathematics and physics, says Yasmin Kopp. “It wasn’t until high school that my interest grew,” the 26-year-old sums up. “Until I got my bachelor’s degree, I couldn’t imagine standing in a lab and experimenting with the optical setups I built myself. It wasn’t until I worked as a student assistant for Professor Pronin, who was instrumental in motivating, supporting and encouraging me, that my interest in scientific research really came about.” So far, she is the only woman in the professorship team.

“I think it is important to advance the equality of women in the natural sciences. That was one of the reasons for me to apply for the fellowship. You can see from my example where things can go if you dare to enter a male-dominated research field as a woman.”

Pro Exzellenzia enables young female scientists to receive a scholarship as well as skills development in the form of career coaching, leadership and application training, body language, empathy or self-assertion, among other things. “I’m looking forward to the workshops, to getting input from experienced female researchers. I’m totally up for that. Above all, the program that Pro Exzellenzia offers here was the reason for me to apply.”