6 papers
Enhanced Valley Polarization via Nonlinear Cascaded Quantum-Geometric Selection Rules
Quentin Courtade, Sotirios Fragkos, Dominique Descamps +4
The quantum geometric properties of Bloch electrons fundamentally govern light-matter interactions and optical selection rules in solids. In semiconducting transition-metal dichalc…
Dielectric Screening in Electromagnetic Dressing of Semiconductors
Quentin Courtade, Umberto Dellasette, Sotirios Fragkos +4
Nonequilibrium manipulation of quantum materials via electromagnetic dressing provides an on-demand route to tailoring electronic band structures through Floquet engineering. Time-…
Electron-phonon-dominated charge-density-wave fluctuations in TiSe accessed by ultrafast nonequilibrium dynamics
Sotirios Fragkos, Hibiki Orio, Nina Girotto Erhardt +17
The complex phase diagram of 1T-TiSe2 consists of a charge density wave (CDW) below 200 K, and CDW fluctuations of still unknown origin at higher temperatures. Here, we use time-re…
Time- and Polarization-Resolved Extreme Ultraviolet Momentum Microscopy
Sotirios Fragkos, Quentin Courtade, Olena Tkach +7
We report the development of an instrument combining an ultrafast, high-repetition-rate, polarization-tunable monochromatic extreme ultraviolet (XUV, 21.6 eV) beamline and a next-g…
A frustrated antipolar phase analogous to classical spin liquids
G. Bastien, D. RepÄek, A. Eliáš +17
The study of magnetic frustration in classical spin systems was motivated by the prediction and discovery of classical spin liquid states. These uncommon magnetic phases are charac…
Quasi-two-dimensional ferromagnetism in the triangular magnet EuAlO
G. Bastien, Q. Courtade, A. Eliáš +6
We report ferromagnetic ordering at K in the quasi-two dimensional magnet EuAlO with large spins . This ferromagnetic state was characteri…