TY  - GEN
KW  - spin physics; atomic physics; quantum simulation; quantum dynamics
ID  - heidok31511
Y1  - 2022///
CY  - Heidelberg
TI  - Realization of a Heisenberg XXZ spin system using Rydberg atoms
N2  - In this thesis, we present the realization of an isolated Heisenberg XXZ spin 1/2 system with an off-diagonal
disorder in the coupling constants using cold atoms in highly excited Rydberg states. We select a set of
Rydberg states that interact via van der Waals interaction which can be mapped onto an interacting spin
system. We investigate the out-of-equilibrium dynamics of the spin system after it has been initialized in
a fully magnetized state. Following unitary evolution governed by the Heisenberg spin Hamiltonian, we
measure the magnetization as a function of the evolution time. By fitting a stretched exponential function
to the resulting magnetization dynamics be obtain a stretched exponent of ? = 0.32 revealing a slow
relaxation of the spin system, similar to what is found in spin glasses. By choice, the initial state is an
eigenstate of the mean-field Hamiltonian and thus the observed relaxation indicates that the dynamics are
triggered by quantum fluctuations. We find that varying the distribution of coupling constants by means
of the so-called dipole blockade effect has no impact on the stretching exponent indicating that it is
a universal parameter of the system independent of the microscopic details for the range of disorder
explored in the experiment. It also allows us to combine the different datasets by re-scaling the time
domain with the characteristic interaction strength. The combined datasets expand our measurements to
two orders of magnitude in the re-scaled time-domain showing that slow dynamics is a persistent effect
for long evolution times.
A1  - Ferracini Alves, Renato
AV  - public
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/31511/
ER  -