Seminar: “Exotic Ising dynamics in a 1D Bose-Hubbard model”,Luis Seabra, MPI-PKS

Seminar hosted by Theory of Quantum Matter (Nic Shannon) Unit :

Title: “Exotic Ising dynamics in a 1D Bose-Hubbard model”

Speaker: Dr. Luis Seabra, Max-Planck Institute for the Physics of Complex Systems (MPI-PKS), Dresden

Date: Thursday 14^th March

Time: 10:00am - 11:00am

Venue: Meeting Room D015, Lab 1

Abstract:

We explore the dynamical properties of a one-dimensional Bose-Hubbard model, where two different bosonic species interact via Feshbach resonance. A brief introduction to simulating the ground state and dynamical properties of 1D systems using Matrix-Product states is given.

We focus on the region in the phase diagram which is described by an effective, low-energy ferromagnetic Ising model in both transverse and longitudinal fields. In this regime, we numerically calculate the dynamical structure factor of the Bose-Hubbard model using the Time-Evolving Block Decimation method.

  In the ferromagnetic phase, we observe both the continuum of excitations and the bound states in the presence of a longitudinal field. Near the Ising critical point, we observe the celebrated $E_8$ mass spectrum in the excited states. We also point out possible measurements which could be used to detect these excitations in an optical lattice experiment.