TY  - GEN
ID  - heidok34460
Y1  - 2024///
TI  - Correlations in two-dimensional few-fermion systems
CY  - Heidelberg
AV  - public
N2  - This thesis presents experiments with few-fermion systems in quasi-2D. Starting with spin-balanced systems, the emergence of a few-body precursor of a phase transition is presented. The microscopic origins of the precursor, namely Pauli blocking and Cooper pair formation at the Fermi surface, are observed using single particle microscopy of in situ momenta. Using matterwave techniques, a microscopy scheme to measure in situ positions of particles in a regime where the system size is smaller than the effective imaging resolution is presented. This matterwave microscope is characterized and its performance is demonstrated by measuring correlations across the BEC-BCS crossover in a few-body spin-balanced system. Spin-imbalanced few-fermion systems are then studied. The preparation of such systems in the motional ground state using interaction mediated spin-motion coupling is demonstrated. A simple model system consisting of a single impurity immersed in a few-body Fermi sea is studied and correlations of in situ positions beyond second order are used to infer a few-body precursor of the polaron-molecule transition. The effect of fermion number on the molecular state and the stability of the metastable excited state are studied. The effect of mismatched Fermi surfaces at finite impurity concentrations on the center-of-mass(COM) momentum of pairs are then explored by accessing correlations.
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/34460/
A1  - Subramanian, Keerthan
ER  -