Waveguide Quantum Electrodynamics in Superconducting Circuits
Licentiate thesis, 2019

In the last two decades, the field of circuit quantum electrodynamics, that studies the interaction between superconducting qubits and 1-dimensional waveguides, has been of great interest. It provides a great potential to build quantum devices, which are important for quantum computing, quantum communication and quantum information. The restriction to one dimension decreases losses and information can be transferred efficiently. Superconducting qubits are artificial atoms that consist of a non-linear Josephson element and work in the microwave regime. These superconducting qubits make on-chip tunable quantum experiments possible.
In the appended paper, we investigate the spontaneous emission of an initially excited artificial atom (superconducting transmon qubit) which is capacitively coupled to a semi-infinite transmission line (atom in front of a mirror). We can choose the distance to the mirror arbitrarily so the interaction with the reflected field is delayed if the qubit is far away from the mirror and we have to take time-delay effects into account. We derive equations of motion for the transmon by circuit quantization and solve them semi-classically. In this thesis we give an introduction to circuit quantization, transmission lines and superconducting qubits. Then we discuss the methods and results of the appended paper which are based on the topics introduced.

Superconducting Qubits

Artificial Atoms

Waveguide Quantum Electrodynamics

Circuit Quantum Electrodynamics

Quantum Optics

Kollektorn, MC2, Kemivägen 9, Chalmers
Opponent: Witlef Wieczorek, Quantum Technolgy Laboratory


Emely Wiegand

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

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Subject Categories

Other Mathematics

Other Physics Topics

Condensed Matter Physics


Chalmers University of Technology

Kollektorn, MC2, Kemivägen 9, Chalmers

Opponent: Witlef Wieczorek, Quantum Technolgy Laboratory

More information

Latest update