Experimental Quantum Electrodynamics

V Kasper, F Hebenstreit, Fred Jendrzejewski +2 more

We discuss the experimental engineering of model systems for the description of quantum electrodynamics (QED) in one spatial dimension via a mixture of bosonic 23 Na and fermionic 6 Li atoms. The local gauge symmetry is realized in an optical superlattice, using heteronuclear boson–fermion spin-changing interactions which preserve the total spin in every local collision. We consider a large number of bosons residing in the coherent state of a Bose–Einstein condensate on each link between the fermion lattice sites, such that the behavior of lattice QED in the continuum limit can be recovered. The discussion about the range of possible experimental parameters builds, in particular, upon experiences with related setups of fermions interacting with coherent samples of bosonic atoms. We determine the atomic system’s parameters required for the description of fundamental QED processes, such as Schwinger pair production and string breaking. This is achieved by benchmark calculations of the atomic system and of QED itself using functional integral techniques. Our results demonstrate that the dynamics of one-dimensional QED may be realized with ultracold atoms using state-of-the-art experimental resources. The experimental setup proposed may provide a unique access to longstanding open questions for which classical computational methods are no longer applicable.

Donald Bowen

F. J. Dyson

Hong‐Fu Wang, Ai‐Dong Zhu, Shou Zhang +1 more

We propose a scheme for implementing discrete quantum Fourier transform in cavity quantum electrodynamics (QED). The experimental implementation is appealingly simple because the combined effect of the complex controlled- R k gate and SWAP gate operations required for implementing discrete quantum Fourier transform in the naive quantum circuit is replaced by the one-step CR k S gate, which can be directly implemented via atom–cavity interaction with the assistance of classical fields. We propose the detailed experimental procedure and analyze the experimental feasibility. The experimental implementation of the scheme would show the full power of quantum algorithm and would open wide prospects for more complicated quantum computation with atoms in QED.

Colin, Samuel

We show that it is possible to obtain a realistic and deterministic model, based on a previous work of John Bell, which reproduces the experimental predictions of the orthodox interpretation of quantum electrodynamics.

John Dirk Walecka