Parts | Days | Selection | Search | Updates | Downloads | Help

Q: Fachverband Quantenoptik und Photonik

Q 59: Quantum Gases (Bosons) VI

Q 59.7: Talk

Thursday, March 8, 2018, 12:00–12:15, K 2.020

Entanglement entropy across quantum phases of Ultracold Bosons with incommensurate optical lattice due to cavity backaction — •Shraddha Sharma¹, Astrid E. Niederle², and Giovanna Morigi¹ — ¹Theoretical Physics, Saarland University, Campus E2.6, D-66123 Saarbrucken, Germany — ²Fraunhofer Institute for Experimental Software Engineering IESE, Germany

We consider a bosonic gas in a two-dimensional optical lattice. The atoms interact via s-wave scattering and via long range interactions induced by the coupling with a cavity. We determine the phase diagram when the optical lattice wavelength is incommensurate with the cavity mode wavelength using a mean-field ansatz. In this regime we observe, in addition to the Mott-insulator and the superfluid, also a Bose-Glass and a superglass phase, where the density distribution supports the formation of a stable intracavity field. We explore the behaviour and scaling of entanglement entropy and of entanglement spectrum at the phase transitions using a controlled perturbative expansion above the mean-field ground state.