Speaker's Brief Introduction：Jörg Schmiedmayer is a Professor of Experimental Physics at the Faculty of Physics at the TU-Wien, Vienna, Austria. He was a founding member of the Vienna Centre for Quantum Science and Technology. Schmiedmayer is one of the pioneers of matter wave interferometry and quantum simulation science. His invention of micro traps for neutral atoms and the AtomChip triggered a new field of research, micro-manipulation of atoms, ions and molecules. His research on non equilibrium evolution and relaxation started a new direction in many body quantum science and continues to inspire new research directions world wide. His detailed analysis of correlations in many body quantum systems started a new field in quantum information science: quantum simulation of quantum field theories and emerging quantum simulators which have to be contrasted with simple building the hamiltonian directly in the lab as in Hubbard models. He is a recipient of several prestigious grants and awards, including the Wittgenstein Prize. He is full member of the Austrian Academy of Sciences.
Abstract: Generalized Hydro Dynamics (GHD) is a novel, very powerful tool to describe 1d systems [1]. After a very brief introduction, I will first present a way to extend GHD to the dimensional cross over regime [2] and highlight the experimental tests of standard and extended GHD. In the second part of my talk, I will highlight how GHD can give us a much-improved understanding of the excitations, their transport properties and their decay/dephasing in a 1d Bose gas, and thereby highlighting the relationship between many-body interactions and dimensionality. In the first of our experiments, we prepare a single mode of excitations and watch it decay [3]. We find that the observed decay of the excitations is perfectly described with GHD and 1D behaviour can extend deep into the three-dimensional (3D) crossover. Our observations demonstrate that the fundamental excitations are not phonons but rapidities assuming fermionic statistics, despite the gas being purely bosonic [3]. The rapid damping of phonons can 1d can be understood as the dephasing the rapidities. In a second experiments we study transport of charge and energy in 1d systems and for the first-time measure Drude weights [4], thereby linking the cold atom quantum simulator directly to the observables used to characterise transport in solid state systeeems.
Supported by DFG-FWF: SFB ISOQUANT and the ERC-AdG EmQ.
[1] B. Doyon, et al., PRX in print (2025), arXiv:2311.03438.
[2] F. Moller, et al., Phys.Rev.Lett. 126, 090602 (2021)
[3] F. Cataldini et al., Phys. Rev. X 12, 041032 (2022)
[4] P. Schüttelkopf, et al., arXiv:2406.17569 (2024)