Quantum Computation Toolbox for Decoherence‐Free Qubits Using Multi‐Band Alkali Atoms

Abstract

Protocols for designing and manipulating qubits with ultracold alkali atoms in 3D optical lattices are introduced. These qubits are formed from two‐atom spin superposition states that create a decoherence‐free subspace immune to stray magnetic fields, dramatically improving coherence times while still enjoying the single‐site addressability and Feshbach resonance control of state‐of‐the‐art alkali atom systems. The protocol requires no continuous driving or spin‐dependent potentials, and instead relies upon the population of a higher motional band to realize naturally tunable in‐site exchange and cross‐site superexchange interactions. As a proof‐of‐principle example of their utility for entanglement generation for quantum computation, it is shown that the cross‐site superexchange interactions can be used to engineer 1D cluster states. Explicit protocols for experimental preparation and manipulation of the qubits are also discussed, as well as methods for measuring more complex quantities such as out‐of‐time‐ordered correlation functions (OTOCs).

Document Details

Document Type
Pub Defense Publication
Publication Date
Apr 27, 2020
Source ID
10.1002/qute.201900132

Entities

People

  • Ana María Rey
  • Joseph H. Thywissen
  • Mikhail Mamaev

Organizations

  • Air Force Office of Scientific Research
  • National Institute of Standards and Technology
  • National Science Foundation
  • Natural Sciences and Engineering Research Council
  • University of Toronto

Tags

Fields of Study

  • Physics

Readers

  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.
  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.

Technology Areas

  • Quantum Computing
  • Quantum Science - Quantum Dots