Cat states in a driven superfluid: role of signal shape and switching protocol
Departamento de Física de Materiales, Universidad Complutense de Madrid, 28040, Madrid, Spain
2 Department of Physics, Humboldt-Universität zu Berlin, Newtonstr. 15, 12489, Berlin, Germany
Accepted: 5 January 2021
Published online: 14 April 2021
We investigate the behavior of a one-dimensional Bose–Hubbard model whose kinetic energy is made to oscillate with zero time-average. The effective dynamics is governed by an atypical many-body Hamiltonian where only even-order hopping processes are allowed. At a critical value of the driving, the system passes from a Mott insulator to a superfluid formed by a cat-like superposition of two quasi-condensates with opposite non-zero momenta. We analyze the robustness of this unconventional ground state against variations of a number of system parameters. In particular we study the effect of the waveform and the switching protocol of the driving signal. Knowledge of the sensitivity of the system to these parameter variations allows us to gauge the robustness of the exotic physical behavior.
© The Author(s), under exclusive licence to EDP Sciences, Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2021