Hamiltonian engineering of spin-orbit–coupled fermions in a Wannier-Stark optical lattice clock

Authors: Alexander Aeppli, Anjun Chu, Tobias Bothwell, Colin J. Kennedy, Dhruv Kedar, Peiru He, Ana Maria Rey, Jun Ye

Published: 2022-10-12

DOI: 10.1126/sciadv.adc9242

Source: Full article


Abstract

Engineering a Hamiltonian system with tunable interactions provides opportunities to optimize performance for quantum sensing and explore emerging phenomena of many-body systems. An optical lattice clock based on partially delocalized Wannier-Stark states in a gravity-tilted shallow lattice supports superior quantum coherence and adjustable interactions via spin-orbit coupling, thus presenting a powerful spin model realization. The relative strength of the on-site and off-site interactions can be tuned to achieve a zero density shift at a “magic” lattice depth. This mechanism, together with a large number of atoms, enables the demonstration of the most stable atomic clock while minimizing a key systematic uncertainty related to atomic density. Interactions can also be maximized by driving off-site Wannier-Stark transitions, realizing a ferromagnetic to paramagnetic dynamical phase transition.