Quantum Hardware II: cQED and cirQED

  • Bernard Zygelman


We introduce the vacuum Maxwell equations and use them to describe electromagnetic fields trapped in a cavity. Boundary conditions for the cavity are shown to lead to standing wave solutions which we quantize to construct cavity QED, a quantum theory for those fields. We insert a rotor into the cavity and are led to a quantum description of a rotor(atom) qubit coupled to a quantized electromagnetic field. We derive the Jaynes-Cummings Hamiltonian and find its approximate eigenvalues and eigenvectors in the strong atom-radiation coupling regime. We show how artificial atoms, composed of superconducting Josephson junctions, interact with microwave line-resonator photons, thus allowing a circuit analog of cavity QED. We discuss how the latter is described with electrical circuit terminology.


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© Springer Nature Switzerland AG 2018

Authors and Affiliations

  • Bernard Zygelman
    • 1
  1. 1.Department of Physics and AstronomyUniversity of NevadaLas VegasUSA

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