Kristinn Juliusson
Early Stage Researcher

CEA-Saclay, France

Academic Background

Between 2007 and 2010 I studied Physics at undergraduate level at the University of Iceland where I joined Professor Snorri Ingvarsson’s group. During two summers I studied antiferromagnetic layers and surface magneto-optical measurement techniques.

In the fall of 2010 I started my masters studies at ETH Zurich. I soon joined the quantum device lab of Professor Andreas Wallraff for a semester thesis on an imaging/excitation laser system for break junctions. Having taken both experimental and theoretical courses on quantum information, I decided to focus on the experimental side for my thesis. I re-joined the quantum device lab where I worked with Dr. Johannes Fink on circuit QED in 3D cavities. Following my graduation in the spring of 2011 I stayed on as a research assistant in the quantum device lab for 3 months.

In January 2013 I started my PhD studies in the Quantronics group at CEA Saclay under the supervision of Dr. Daniel Esteve, Dr. Denis Vion and Dr. Patrice Bertet.

Description of Work

I will continue working on circuit QED in 3D cavities as I did in Zurich and try to reach the state of the art qubit and cavity lifetimes. Building on that, I will aim to make a system with parameters such that I can observe quantum Zeno dynamics (QZD) (DOI: 10.1103/PhysRevLett.105.213601). QZD is based on the quantum Zeno effect (QZE) where a quantum mechanical system is fixed it a certain state by continuous or frequent projections onto that state. In QZD one projects the system not onto a state but a subspace of its Hilbert space. Using QZD exotic states of light can be engineered (e.g. Schrodinger-cat states). One benefit of using circuit QED is for this experiment is the fact that the artificial atom (e.g. Transmon) is constantly present in the cavity. This along with high enough cavity lifetimes should make observation of QZD possible.

Publications

Multiplexed Readout of Transmon Qubits with Josephson Bifurcation Amplifiers
V. Schmitt, X. Zhou, K. Juliusson, A. Blais, P. Bertet, D. Vion, D. Esteve
arxiv.org/abs/1409.5647, accepted in Phys. Rev. A

Experimental realization of non-Abelian non-adiabatic geometric gates
A. A. Abdumalikov, J. M. Fink, K. Juliusson, M. Pechal, S. Berger, A. Wallraff & S. Filipp
Nature (2013) doi:10.1038/nature12010