SAMOP 2023 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
A: Fachverband Atomphysik
A 27: Poster III
A 27.13: Poster
Thursday, March 9, 2023, 16:30–19:00, Empore Lichthof
Ultracold Plasma: Many-body dynamics across the ionization threshold — •Julian Fiedler1,2, Mario Großmann1,2, Jette Heyer1,2, Linn Hamester2, Amir Khan2, Klaus Sengstock1,2, Markus Drescher1,2, Philipp Wessels-Staarmann1,2, and Juliette Simonet1,2 — 1The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany — 2Center for Optical Quantum Technologies, University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
Ultrashort laser pulses provide pathways for manipulating atomic quantum gases on femtosecond timescales. We use a single ultrashort laser pulse of tunable wavelength to ionize a cloud of ultracold 87Rb atoms via a two-photon process and detect the ionization fragments.
At high excess energies above the ionization threshold, fast electrons are created and we observe the formation of an ultracold microplasma with a rapid electron cooling on picosecond timescales, where the orbit of the electrons lies outside the dense ionic core. Lowering the electron excess energy allows creating a plasma were the electron trajectories predominantly lie inside the ionic core.
By tuning the two-photon excitation energy below the ionization threshold, we create a dense ensemble of Rydberg atoms, which circumvents the Rydberg blockade due to the large bandwidth of the laser pulse. The subsequent dynamics is governed by collisional ionization of the Rydberg atoms and formation of an ultracold plasma. The results are compared to classical molecular dynamics simulations.