Decoherence-Free Interaction between Giant Atoms in Waveguide Quantum Electrodynamics
Journal article, 2018

In quantum-optics experiments with both natural and artificial atoms, the atoms are usually small enough that they can be approximated as pointlike compared to the wavelength of the electromagnetic radiation with which they interact. However, superconducting qubits coupled to a meandering transmission line, or to surface acoustic waves, can realize "giant artificial atoms" that couple to a bosonic field at several points which are wavelengths apart. Here, we study setups with multiple giant atoms coupled at multiple points to a one-dimensional (1D) waveguide. We show that the giant atoms can be protected from decohering through the waveguide, but still have exchange interactions mediated by the waveguide. Unlike in decoherence-free subspaces, here the entire multiatom Hilbert space (2N states for N atoms) is protected from decoherence. This is not possible with "small" atoms. We further show how this decoherence-free interaction can be designed in setups with multiple atoms to implement, e.g., a 1D chain of atoms with nearest-neighbor couplings or a collection of atoms with all-to-all connectivity. This may have important applications in quantum simulation and quantum computing.

Author

Anton Frisk Kockum

RIKEN

Göran Johansson

Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics

F. Nori

University of Michigan

RIKEN

Physical Review Letters

0031-9007 (ISSN) 1079-7114 (eISSN)

Vol. 120 14 140404

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Subject Categories

Atom and Molecular Physics and Optics

Other Physics Topics

Theoretical Chemistry

DOI

10.1103/PhysRevLett.120.140404

More information

Latest update

6/26/2020