Quantum Electrodynamics with Ultracold Atoms

Transcription

1 Quantum Electrodynamics with Ultracold Atoms Valentin Kasper Harvard University Collaborators: F. Hebenstreit, F. Jendrzejewski, M. K. Oberthaler, and J. Berges

2 Motivation for QED (1+1) Theoretical Motivation Confinement Chiral symmetry breaking Schwinger Effect Non-equilibrium physics Experimental Motivation Observation of Schwinger Effect One dimensional system No plaquette terms Talk by Florian Hebenstreit Talk by Fred Jendrzejewski Strong Field Physics AMO Valentin Kasper, Harvard University 2

3 Aim of this Talk Can we observe the Schwinger Effect in an ultracold atom setup? Valentin Kasper, Harvard University 3

4 Outline Experimental Realization of QED in (1+1) Schwinger Effect in a cold atom setup Conclusion Valentin Kasper, Harvard University 4

5 Ways to engineer gauge theories Different Strategies Global Symmetry to Local Symmetry Zohar, Cirac, Reznik PRA 88.2 (2013): Energy Penalty Banerjee, D., et al, PRL (2012): Dissipative Driving Stannigel, PRL (2014): Digital Quantum Simulation Zohar, et al. arxiv: (2016). Tagliacozzo, L., et al., Nature communications 4 (2013) Valentin Kasper, Heidelberg University 5

6 Kogut et al., PRD, vol 11, 2 Hamiltonian of QED (1+1) Quantum Electrodynamics Electric Field Mass Term Interaction Term Gauss s Law Valentin Kasper, Harvard University 6

7 Zohar, Cirac, Reznik PRA 88.2 (2013): Mapping on atomic systems Electric Field Mass Term Interaction Term Valentin Kasper, Harvard University 7

8 Zohar, Cirac, Reznik PRA 88.2 (2013): Starting Point of Ultracold Atom Setup Kinetic Energy Potential Energy Interaction Energy Valentin Kasper, Harvard University 8

9 1D and Lattice Structure One dimensional via radial confinement Staggered structure via superlattice Valentin Kasper, Harvard University 9

10 Magnetic Field Hyperfine Splitting Why only two lines? Valentin Kasper, Harvard University 10

11 Starting Point of Ultracold Atom Setup Kinetic Energy Potential Energy Interaction Energy Valentin Kasper, Harvard University 11

12 Interaction Terms (i) Local, F conserving interaction Coupling constant Projection operator Valentin Kasper, Harvard University 12

13 Interaction Terms (ii) Interaction Part Valentin Kasper, Harvard University 13

14 Interaction Terms (iii) F B F Lattice sites and overlap integral Valentin Kasper, Harvard University 14

15 Bosonic Interactions Staggered Structure of Bosons Valentin Kasper, Harvard University 15

16 Aim of this Talk Electric Field Mass Term Interaction Term Valentin Kasper, Harvard University 16

17 Fermion Interactions Density-density Interactions Gauss s law eliminates this term Valentin Kasper, Harvard University 17

18 Bose - Fermi Interaction Spin changing terms Gauss s Law eliminates elastic terms

19 Mass Term / Detuning Sum of three potential energies A) Potential Energy due to Lattice B) Elastic Scattering Contribution C) Detuning due magnetic field and rf Valentin Kasper, Harvard University 19

20 Outline Experimental Realization of QED in (1+1) Schwinger Effect in a cold atom setup Conclusion Valentin Kasper, Harvard University 20

21 AMO and HEP connected Identification of coupling constants Valentin Kasper, Harvard University 21

22 Numbers Numbers of Bosons per Links Bose-Bose coupling Bose-Fermi coupling Detuning Effective Bose-Fermi Interaction Boson Tunneling Fermi Tunneling Valentin Kasper, Harvard University 22

23 VK et al, arxiv: Schwinger Pair Production (i) Valentin Kasper, Harvard University 23

24 Schwinger Pair Production (ii) Valentin Kasper, Harvard University 24

25 Outline Experimental Realization of QED in (1+1) Schwinger Effect in a cold atom setup Conclusion Valentin Kasper, Harvard University 25

26 Conclusion Schwinger Effect feasible in cold atom system To do: New Strategies to engineer gauge theories Simplify the proposals Theoretical predictions Valentin Kasper, Harvard University 26