Strong Interaction Between a Single Artificial Atom and Propagating Microwave Photons
Licentiatavhandling, 2011

The realization of a quantum network composed of quantum nodes which process quantum fields and quantum channels to transfer quantum information has recently been proposed. In recent years, fundamental experiments produced by superconducting circuits suggest that they are promising candidates for realization of a quantum network. Superconducting circuit QED can act as quantum nodes, which can be linked by quantum channels, to transfer flying microwave photons (quantum information) from site to site on chip with high fidelity. Therefore, controlling the propagating microwave photons on chip is an essential step towards realization of a quantum network. In this thesis, we demonstrate a specific quantum node, namely the single photon router. The active element of the router is a single three-level artificial atom, a superconducting transmon type qubit, strongly coupled to a superconducting 1D transmission line. Strong coupling between the artificial atom and propagating microwave photons, revealed in high degree scattering of the resonance waves, has been observed. By exploiting the phenomenon of electromagnetically induced transparency (EIT), we can route a single photon signal from an input port to either of two output ports with an on-off ratio of approximately 90%. The switching time of the router is shown to be a few nanoseconds, consistent with theoretical expectations and the device parameters. Besides the router, we also observed some fundamental phenomenon of single atom, such as strong nonlinearity, anomalous dispersion and the Mollow Triplet. This thesis describes the motivation, theoretical background, design, implementation and the measurement results.

microwave devices

Mollow triplet.

qubit

circuit QED

electromagnetically induced transparency

quantum nodes

transmon

quantum channels

superconductivity

anomalous dispersion

quantum information

microwaves

quantum network

Kollektorn, MC2
Opponent: Prof. David Haviland

Författare

Io Chun Hoi

Chalmers, Mikroteknologi och nanovetenskap (MC2)

Styrkeområden

Nanovetenskap och nanoteknik

Ämneskategorier

Fysik

Elektroteknik och elektronik

Technical report MC2 - Department of Microtechnology and Nanoscience, Chalmers University of Technology

Kollektorn, MC2

Opponent: Prof. David Haviland