Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 86: Surface dynamics
O 86.3: Vortrag
Donnerstag, 12. März 2026, 15:45–16:00, HSZ/0403
Nonadiabatic Energy Loss in Hyperthermal Gas-Surface Scattering: Going Beyond the Mean Field Approximation — •Ash Baldwin1 and Reinhard J. Maurer1,2 — 1University of Vienna, Vienna, Austria — 2University of Warwick, Coventry, United Kingdom
Nonadiabatic energy dissipation is known to play a crucial role in hyperthermal scattering at surfaces, leading to electron-hole pair excitation and highly inelastic scattering. For projectiles with unpaired spins, such as hydrogen atoms, hybridisation with the metal surface results in strong non-adiabatic effects driven by a phase transition in its spin-polarisation. It is known that traditional mean-field descriptions of the resultant nonadiabatic dynamics using methods like MDEF and Ehrenfest dynamics break down in the presence of the transition, leading to divergent energy transfer rates and unphysical stopping powers at the location of the spin transition [Box et al. J. Phys. Chem. Lett. 15, 51 (2024); Lindenblatt et al. Phys. Rev. Lett. 97 (2006)].
Here, we model H/Cu(111) and H/Ag(111) scattering in the presence of on-site correlation in the adsorbate state using the Newns-Anderson Hamiltonian. We go beyond previous works by simulating the dynamics using stochastic trajectory surface hopping methods that capture the coupling between the nuclear and electronic degrees of freedom beyond the mean-field. By systematically classifying scattering regimes, we assess the applicability of mean-field and beyond mean-field methods for predicting nonadiabatic energy loss.
Keywords: Gas-Surface Dynamics; Hyperthermal Scattering; Nonadiabatic Dynamics; Electron Coupling; Phase Transitions