22 citations · 49 across the 16 of their papers we have counts for
17 papers
Chiroptical Valleytronic in SnSe
Yiming Pan, Sotirios Fragkos, Umberto Dellasette +5
Quantum geometric properties of Bloch electrons play a central role in governing light-matter interactions and transport phenomena in solids. Here, we report quantum-geometric chir…
Phonon-induced pseudogap phase in TiSe
Sotirios Fragkos, Nina Girotto Erhardt, Evgenia Symeonidou +9
To comprehend quantum ordered states, such as charge density waves (CDW), in layered transition metal dichalcogenides (TMDCs), it is essential to uncover their underlying normal st…
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…
Symmetry-Driven Floquet Engineering in Multivalley SnS
Sotirios Fragkos, Benshu Fan, Umberto De Giovannini +5
Coherent interactions between time-periodic electromagnetic fields and materials offer a powerful platform for engineering light-matter hybrid Floquet states with tailored function…
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-…
Accurate and efficient simulation of photoemission spectroscopy via Kohn-Sham scattering states
Gian Parusa, Sotirios Fragkos, Samuel Beaulieu +1
We introduce an efficient first-principles framework for simulating angle-resolved photoemission spectroscopy (ARPES) based on the direct computation of photoelectron states as sol…
Ultrafast Strongly Anisotropic Valleytronics in SnSe
Yiming Pan, Sotirios Fragkos, Dominique Descamps +3
Valleytronics aims to control electrons in a valley-specific manner for quantum information manipulation. Due to their strong in-plane anisotropy, which enables polarization-contro…
Ultrafast Nonequilibrium Enhancement of Electron-Phonon Interaction in 2H-MoTe
Nina Girotto Erhardt, Sotirios Fragkos, Dominique Descamps +4
Understanding nonequilibrium electron-phonon interactions at the microscopic level and on ultrafast timescales is a central goal of modern condensed matter physics. Combining 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…
Control of intervalley scattering in BiTe via temperature-dependent band renormalization
A. Jabed, F. Goto, B. Frimpong +11
The control of out-of-equilibrium electron dynamics in topological insulators is essential to unlock their potential in next-generation quantum technologies. However, the role of t…
Floquet-Bloch Valleytronics
Sotirios Fragkos, Baptiste Fabre, Olena Tkach +6
Driving quantum materials out-of-equilibrium makes it possible to generate states of matter inaccessible through standard equilibrium tuning methods. Upon time-periodic coherent dr…
Excited States Band Mapping and Ultrafast Nonequilibrium Dynamics in Topological Dirac Semimetal 1T-ZrTe
Sotirios Fragkos, Evgenia Symeonidou, Emile Lasserre +7
We performed time- and polarization-resolved extreme ultraviolet momentum microscopy on topological Dirac semimetal candidate 1T-ZrTe. Excited states band mapping uncovers the…
Strong-field ionization of chiral molecules with bicircular laser fields : sub-barrier dynamics, interference, and vortices
Samuel Beaulieu, Sylvain Larroque, Dominique Descamps +5
Strong-field ionization by counter-rotating two-color laser fields produces quantum interference between photoelectrons emitted on the leading and trailing edges of the laser field…
Multimode Objective Lens for Momentum Microscopy and XPEEM: Experiments
O. Tkach, S. Fragkos, D. Biswas +37
A new type of objective lens has recently been proposed for use in X-ray photoemission electron microscopes (XPEEMs) and momentum microscopes. Adding a ring electrode concentric wi…
Role of Spin-Orbit Coupling in High-order Harmonic Generation Revealed by Super-Cycle Rydberg Trajectories
Nicola Mayer, Samuel Beaulieu, Alvaro Jimenez-Galan +7
High-harmonic generation is typically thought of as a sub-laser-cycle process, with the electron's excursion in the continuum lasting a fraction of the optical cycle. However, it w…
Multiphoton Photoelectron Circular Dichroism of Limonene with Independent Polarization State Control of the Bound-Bound and Bound-Continuum Transitions
Samuel Beaulieu, Antoine Comby, Dominique Descamps +5
Photoionization of randomly oriented chiral molecules with circularly polarized light leads to a strong forward/backward asymmetry in the photoelectron angular distribution. This c…