News

New Publication

N. Hofmann, L. Weigl, J. Gradl, N. Mishra, G. Orlandini, S. Forti, C. Coletti, S. Latini, L. Xian, A. Rubio, D. Perez Paredes, R. Perea Causin, S. Brem, E. Malic and I. Gierz: Link between interlayer hybridization and ultrafast charge transfer in WS₂-graphene heterostructures

2D Mater. 10, 035025 (2023)

iopscience.iop.org/article/10.1088/2053-1583/acdaab

Narrowband THz source

We have set up a narrowband THz source that will enable us to study the effects of resonant excitations in the few-tens-of-meV range.

Grating stretcher

We have assembled a transmission grating stretcher that allows us to tune the pulse duration of NIR pulses.

First trARPES with mid-infrared pump

MIR pump 21.7eV probe tr-ARPES data on Sn-intercalated graphene on SiC(0001). The MIR wavelength was 6µm with a field strength of 1MV/cm at the focus. (a) Snapshot of the Dirac cone at negative pump-probe delay before the arrival of the MIR pump pulse. (b) Momentum-integrated energy distribution curve (red) extracted from (a) together with Fermi-Dirac fit (black) to determine the energy resolution of 90meV. (c) Pump-induced changes of the photocurrent with gain in red and loss in blue 100fs after excitation with MIR pump pulses. (d) Counts inside the black box in (c) as a function of pump-probe delay (red) together with fit to determine the temporal resolution of 220fs from the width of the rising edge.

Mid-infrared pump source

We are now generating mid-infrared pump pulses from differency frequency generation in gallium selenide.

First beautiful trARPES-data

2eV pump 21.7eV probe tr-ARPES data on H-intercalated graphene on SiC(0001). (a) Snapshot of the Dirac cone at negative pump-probe delay before the arrival of the 2eV pump pulse. (b) Momentum-integrated energy distribution curve (red) extracted from (a) together with Fermi-Dirac fit (black) to determine the energy resolution of 185meV. (c) Pump-induced changes of the photocurrent with gain in red and loss in blue 50fs after excitation with 2eV pump pulses. (d) Counts inside the black box in (c) as a function of pump-probe delay (red) together with fit to determine the temporal resolution of 170fs from the width of the rising edge.

New publication

R. Krause, S. Aeschlimann, M. Chávez-Cervantes, R. Perea-Causin, S. Brem, E. Malic, S. Forti, F. Fabbri, C. Coletti, and I. Gierz: Microscopic Understanding of Ultrafast Charge Transfer in van der Waals Heterostructures

Phys. Rev. Lett. 127, 276401

link.aps.org/doi/10.1103/PhysRevLett.127.276401

First snow

Synchrotron ARPES data

Synchrotron ARPES data on heterostructure made of monolayer graphene and a 2D metallic Sn layer.

HHG-Emission from Argon gas jet

These are spectra of HHG emission from an Argon gas jet. The different plots represent different monochromator gratings, which offer different combinations of temporal resolution and energy resolution.

First bakeout

The tr-ARPES setup is fully reassembled. We are baking the ARPES chamber to reach the UHV regime.

Lab building finished!

Our completely finished lab building.

Congratulations to Dr. Razvan Krause for sucessfully defending his PhD thesis!

We have moved to our new lab building!

New publication

S. Aeschlimann, S. A. Sato, R. Krause, M. Chávez-Cervantes, U. De Giovannini, H. Hübener, S. Forti, C. Coletti, K. Hanff, K. Rossnagel, A. Rubio, I. Gierz: Survival of Floquet–Bloch States in the Presence of Scattering

Nano Lett. 2021, 21, 12, 5028–5035

https://doi.org/10.1021/acs.nanolett.1c00801

First amplifier is installed

HHG beamline

Optical Tables

The optical tables in our new laboratory are installed.

First laser amplifier

Our first laser amplifier arrived!

New Publication

R. Krause, M. Chávez-Cervantes, S. Aeschlimann, S. Forti, F. Fabbri, A. Rossi, C. Coletti, C. Cacho, Y. Zhang, P. E. Majchrzak, R. T. Chapman, E. Springate, I. Gierz: Ultrafast Charge Separation in Bilayer WS2/Graphene Heterostructure Revealed by Time- and Angle-Resolved Photoemission Spectroscopy

Frontiers in Physics 9, 2021

https://www.frontiersin.org/article/10.3389/fphy.2021.668149

Rapid progress at the construction site

Construction of new lab building

Construction of our new laser lab started in August 2020. This is how it looks today.

ERC project DANCE gets funded!

https://www.uni-regensburg.de/pressearchiv/pressemitteilung/1009093.html