News
How to use spintronics to detect terahertz waves - TRR 227 results published in Science Advances
Using broadband terahertz pulses, researchers at Freie Universität Berlin observed charge-to-spin conversion in the interface region of two nanometer-thin metallic layers at extremely high, terahertz rates. The results enable a new way of detection of terahertz electric fields and provide insight into elusive processes at interfaces.
Apr 09, 2025
New method to control ultrafast spin dynamics in 2D semiconductors - New TRR 227 paper published in Phys. Rev. Lett.
Researchers from FU Berlin (projects B08 and B07) and collaborators from TU Berlin have discovered a new method to control ultrafast spin dynamics in 2D semiconductors. This breakthrough reveals an intricate coupling between spin and momentum of excitons via the Rashba effect with optically controlled magnitude. This effect plays a critical role in defining spin dynamics in 2D semiconductors.
Jan 17, 2025
Dr. Lisa-Marie Kern - KlarText-Preis für Wissenschaftskommunikation 2024
TRR 227 iRTG alumna Dr. Lisa-Marie Kern just received one more prize: The KlarText Award for Science Communication of the Klaus Tschira Foundation . In the category Physics, Lisa-Marie is honored for her outstanding ability to communicate complex scienctifc concepts. - Congratulations again, again and again! All good things come in threes :)
Nov 11, 2024
TRR 227 PI Tom Seifert among Top Minds in Berlin Science
Berlin's newspaper "Der Tagesspiegel" recently presented the top 100 leading scientists of Berlin who made significant impact on research in Berlin in 2024. Among them is Dr. Tom Seifert, TRR 227 PI of project A05.
Nov 08, 2024
TRR 227 is now on Instagram @trr227.fu_berlin
Our TRR 227 is now represented on Instagram with a new channel @trr227.fu_berlin . We will be sharing exciting news about our research as well as recent and upcoming events of the TRR 227.
Oct 24, 2024
Exciton valley character in 2D semiconductors - New TRR 227 paper published in Nature Communications
TRR 227 researchers at Freie Universität Berlin discovered a way to use nanomechanics to control and study hidden intervalley excitons in two-dimensional semiconductors. This breakthrough provides a new material science technique to understand band structure, control spins and valleys, and suggests a new approach for manipulation of spin/valley-based information and its storage.
Sep 09, 2024
TRR 227 PhD student Nele Stetzuhn invited to 73ʳᵈ Lindau Nobel Laureate Meeting
TRR 227 PhD student Nele Stetzuhn had the opportunity to present her talk “Ultrafast, ultrathin, ultratunable: Spintronics in 2D materials" at the 73 rd Lindau Nobel Laureate Meeting in early July 2024.
Jul 15, 2024
Dr. Tom S. Seifert receives Karl Scheel Prize 2024 of the Physikalische Gesellschaft zu Berlin
For his outstanding scientific achievement, Tom S. Seifert, PI of TRR 227 project A05, was awarded with the Karl-Scheel-Preis 2024 of the Physikalische Gesellschaft zu Berlin. - Congratulations!
Jun 20, 2024
Optical control of 4f orbital state in rare-earth metals - TRR 227 results published in Science Advances
Researchers from FU Berlin and HZB (projects A01 and A03) and collaborators show that inelastic 5𝘥-4𝘧 electron-electron scattering leads to excitation of the localized terbium 4𝘧 state out of the ground state multiplet (4 𝘧 ⁸ ⁷𝘍 ₆). Such excitations alter the total angular momentum J and affect the 4𝘧 orbital state, with direct implications for ultrafast magnetization dynamics in 4𝘧 systems.
Apr 18, 2024
ERC Advanced Grant 2024 for Tobias Kampfrath
TRR 227 PI Tobias Kampfrath (projects A05 & B02) at FU Berlin has been awarded with a 2024 Advanced Grant of the European Research Council. A total of 2.5 Mio. EUR comes with this prestigious research grant.
Apr 11, 2024
Dr. Lisa-Marie Kern - SKM Dissertation Prize of the DPG
TRR 227 iRTG alumna Dr. Lisa-Marie Kern received not only the Carl-Raumsauer-Preis 2023 of the Physikalische Gesellschaft zu Berlin , but also very recently she was awarded with the SKM Dissertation Prize of the Deutsche Physikalische Gesellschaft for her outstanding dissertation entitled " Controlled Manipulation of Magnetic Skyrmions: Generation, Motion and Dynamics ". - Fantastic and Congrats again!
Mar 18, 2024
Ultrafast demagnetization through rapid spin-wave generation
Excitation of a ferromagnetic material with a femtosecond laser pulse causes an ultrafast magnetization drop, but the deeper mechanism behind this ultrafast drop has been disputed for many years. Physicists within the CRC/TRR 227 now show that ultrafast generation of non-thermal spin waves can explain a rapid magnetization loss within 200 femtoseconds (fs) consistent with experiments.
Feb 12, 2024
TRR227 hosts Ultrafast Magnetism Conference 2024
TRR227 PIs Martin Weinelt and Stefan Eisebitt serve as Conference Chairs of the Ultrafast Magnetism Conference 2024 , being held at the Henry Ford Building of FU Berlin, 2 - 6 Sept. 2024.
Dec 23, 2023
Dr. Lisa-Marie Kern - Carl Ramsauer Prize 2023 of the Physikalische Gesellschaft zu Berlin
For her outstanding dissertation, Lisa-Marie Kern, a former iRTG member of our TRR 227, was awarded with the Carl-Raumsauer-Preis 2023 of the Physikalische Gesellschaft zu Berlin. - Congratulations!
Nov 22, 2023
Max Born Prize and Medal 2024 for Ingrid Mertig (MLU Halle-Wittenberg)
The Deutsche Physikalische Gesellschaft (DPG) and the Insitute of Physics (IOP) announced the awardee of the Max Born Prize and Medal for the year 2024.
Nov 16, 2023
New B11 project led by Hélène Seiler - Supplementary proposal approved
Hélène Seiler, tenure track W1-W2 professor at the Physics Department of FU Berlin, proposed a new project entitled "Probing exciton structure and dynamics in two-dimensional magnets and spintronic heterostructures". DFG now approved this supplementary project as B11 within our CRC/TRR 227. Funding is granted for year 3 and 4 of the 2 nd funding period and starts January 1, 2024.
Nov 01, 2023
Electrical measurements at picosecond timescale - New TRR 227 paper published in Nano Letters
Latest TRR 227 results of projects B07 and B08 on probing the formation of dark interlayer excitons via ultrafast photocurrent just appeared in the journal Nano Letters of the American Chemical Society
Oct 20, 2023
Terahertz currents launch massive spin rotation in an antiferromagnet - TRR 227 results published in Nature Communications
Researchers of the TRR227 at FU Berlin (projects A05 and B02 of PI Tobias Kampfrath) with collaborators in Mainz and Dresden find that spin dynamics in an antiferromagnetic metal can be excited by terahertz electric rather than magnetic fields. Enhanced by exchange-interaction, the spins are deflected by as much as 30° out of their equilibrium direction. By demonstrating this highly nonlinear response, spin rotation by 90° and, thus, ultrafast writing of an antiferromagnetic bit by terahertz electric currents comes into close reach.
Sep 29, 2023
Orbital currents can go far – TRR 227 results published in Nature Nanotechnology
TRR 227 PI Tom S. Seifert (project A05) and colleagues published their latest work on ultrafast orbital currents in the journal “Nature Nanotechnology”. Using terahertz-emission spectroscopy, the researchers found strong evidence for optically triggered orbital angular momentum currents in Ni|W thin-film stacks. Surprisingly, those currents seem to travel for 10s of nm without undergoing any scattering.
Aug 28, 2023
TRR 227 project leader Dr. Sangeeta Sharma has been appointed as professor in the field of "Theoretical Solid State Physics"
We are delighted to announce that on June 26, 2023, Dr. Sangeeta Sharma has been installed as a professor at FU Berlin, in a joint appointment with the Max Born Institute.
Jul 10, 2023
