Optical setup for performing ultrafast, holographic, chiroptical microscopy.
Photo Credit: © Tobias Schwerdt
Scientific Frontline: Extended "At a Glance" Summary: Ultrafast Holographic Chiroptical Microscopy
The Core Concept: A novel microscopy technique that combines holographic imaging with ultrafast spectroscopy to observe the interaction of light and matter, specifically extremely short-lived electronic and magnetic phenomena.
Key Distinction/Mechanism: Unlike traditional microscopy techniques, this method utilizes a pump-probe approach—where an initial light pulse excites the material and a second pulse records its time-dependent response. This allows for the simultaneous, high-resolution imaging of charge and spin dynamics across large fields of view on timescales ranging from femtoseconds to picoseconds.
Major Frameworks/Components:
- Pump-probe excitation and detection experimental setups.
- Integration of high-resolution holographic imaging.
- Ultrafast spectroscopy to measure time-dependent optical responses.
- Chiroptical methodologies to spatially and temporally track electro-magnetic phenomena.
Branch of Science: Physical Chemistry, Photonics, Nanotechnology, Materials Science, Optoelectronics, and Spintronics.
Future Application: The targeted advancement of complex energy materials, paving the way for sustainable and high-efficiency technologies such as modern solar cells, LEDs, spin-LEDs, and advanced electronic components.
Why It Matters: By generating time-resolved "films" of electron dynamics on the micrometer scale, this technique offers unprecedented insights into how light-induced processes change in response to a material's structural composition, accelerating the design of durable, next-generation energy technologies.
Research Team from Heidelberg and Milan Develops Novel Microscopy Technique to Study Energy Materials
An extremely fast microscopy method for researching the interaction of light and matter makes it possible to study optical processes on very short timescales. To this end, a German-Italian research team is combining holographic imaging with ultrafast spectroscopy in an innovative way. In this manner, even extremely short-lived electronic and magnetic phenomena—which play a major role in the development and application of novel energy materials—can be observed. The research was conducted as part of an international collaboration among scientists from the Institute for Physical Chemistry at Heidelberg University, the Polytechnic University of Milan, and the Institute for Photonics and Nanotechnologies in Milan, Italy.
At the heart of the research is a pump-probe microscope, which is used to conduct so-called excitation and detection experiments. In this process, the material under investigation is first excited by a short light pulse, while a second pulse records the time-dependent response. By comparing measurements taken with the excitation on and off, researchers can accurately reconstruct these processes. "Combining holographic imaging with ultrafast spectroscopy allows us to spatially resolve electronic and magnetic dynamics and track them on timescales ranging from femtoseconds to picoseconds," explains Dr. Julia Anthea Gessner, who conducts research as a project leader in Collaborative Research Center 1249, "N-Heteropolycycles as Functional Materials," and as a group leader at the Institute for Physical Chemistry.
The innovative method developed by the German-Italian research team makes it possible to simultaneously image ultrafast electromagnetic phenomena across large fields of view, explains Dr. Martin Hörmann of the Polytechnic University of Milan. Unlike other microscopy techniques, this enables the imaging of areas on the micrometer scale and the generation of time-resolved "films" of the charge and spin dynamics of electrons. In addition, light-induced changes in the optical properties of materials can be made visible in this way. "Our chiroptical approach thereby opens up entirely new possibilities for directly observing dynamic processes in complex materials," says Dr. Hörmann, who played a key role in the current research along with Dr. Gessner and doctoral candidate Federico Visentin.
This high-resolution, ultrafast imaging technique is intended primarily for use with energy materials. These materials are relevant to sustainable technologies such as solar cells, LEDs, spin-LEDs, and innovative electronic components. "The microscopy technique provides new insights into ultrafast optical processes, in particular with respect to how they change in response to the composition and structure of materials," emphasizes Prof. Dr. Felix Deschler, who conducts research at Heidelberg University's Institute for Physical Chemistry. According to Prof. Dr. Franco V. A. Camargo, a scientist at the Institute for Photonics and Nanotechnologies in Milan, research into the interaction of light and matter can provide important insights for the development of efficient and durable components for optoelectronics and spintronics.
Funding: The research was funded by the European Union. It was carried out as part of the Starting Grants awarded to Prof. Deschler and Prof. Camargo by the European Research Council (ERC).
Published in journal: Nature Photonics
Title: Ultrafast holographic chiroptical microscopy
Authors: Martin Hörmann, Federico Visentin, Julia A. Gessner, Philipp Kollenz, Shangpu Liu, Markus Heindl, Felix Deschler, Giulio Cerullo, and Franco V. A. Camargo
Source/Credit: Universität Heidelberg
Edited by: Scientific Frontline
Reference Number: phy052826_01