physics
recent research
Continuous-variable qubit states
Please have a go with my cv qubit space flight simulator! It is science, it is fun - what can you lose?
Using a squeezed vacuum source and an advanced photon subtraction technique, we succeeded in generating a large range of different superpositions of squeezed vacuum and squeezed single-photon states. These states can be interpreted as qubits with continuous-variable basis states.
The following animation illustrates this qubit space as a Bloch sphere. Each experimentally obtained state is represented by its Wigner function at the location on the Bloch sphere corresponding to its superposition parameters.
I have also developed an interactive applet that allows you to move around in the qubit space and investigate each state in detail. Go to the cv qubit applet here.
academic history
Full CV for download- 1999–2003
- Bachelor studies in physics and mathematics at University of Copenhagen.
- 2003–2005
- Master studies in physics. My thesis work was carried out in the Quantop group at the Niels Bohr Institute, University of Copenhagen.
- 2005–2008
- PhD studies in experimental quantum optics at Quantop under the supervision of Prof. Eugene Polzik.
- March–May 2006
- Research exchange student in the Furusawa laboratory at the University of Tokyo.
- October 2008–September 2011
- Limited term researcher (post doc) in the Quantum ICT Group at NICT (National Institute of Information and Communications Technology) in Koganei, Tokyo.
- September 2011–
- Post doc in the Quantum Information Group at DTU (Technical University of Denmark) in Lyngby, Denmark.
My theses for download
- Master thesis
- Nonclassical light source for quantum networks [ pdf, 3.4 MB ]
- PhD thesis
- Generation of single photons and Schrödinger kitten states of light
[ DOI:10.6074/m9.figshare.1328405 | pdf, 11.2 MB ]
publications
Journal articles
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Increasing the photon collection rate from a single NV center with a silver mirror
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Assessments of macroscopicity for quantum optical states
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Heralded generation of a micro-macro entangled state
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Quantum tele-amplification with a continuous-variable superposition state
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Amplification of realistic Schrödinger-cat-state-like states by homodyne heralding
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Displacement-enhanced entanglement distillation of single-mode-squeezed entangled states
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Breakdown of the classical description of a local system
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Photon subtraction from traveling fields - recent experimental demonstrations
- pdf ©NII
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Engineering of optical continuous-variable qubits via displaced photon subtraction: multimode analysis
- pdf ©T&F
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Optical continuous-variable qubit
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Entanglement distillation from Gaussian input states
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Time gating of heralded single photons for atomic memoriesDiscussed in Editor's Choice in Science 327 no. 5963.
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High purity bright single photon source
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Time-gated Einstein-Podolsky-Rosen correlation
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Generation of a superposition of odd photon number states for quantum information networks
In conference proceedings, etc.
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Continuous variable qubit state engineering
- pdf ©AIP
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Quantum interface between light and atomic ensemblesLaser Spectroscopy. Proceedings of the XVIII ICOLS 2007, Eds. L. Hollberg, J. Bergquist, M. Kasevich, World Scientific (2008)
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Narrow bandwidth optical Schrödinger kitten states and single photonsProceedings of the 8th International Conference on QCMC 2006, Eds. O. Hirota, J. H. Shapiro, and M. Sasaki (2007)
Other articles
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Two become oneNews & Views article covering the paper Joining the quantum state of two photons into one by Vitelli et al.
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Bridging discrete and continuous variables in quantum informationOptics in 2010 special issue that "highlights the most exciting peer-reviewed optics research to have emerged over the past 12 months," with our figure on the front cover and with a link to the interactive applet we made to illustrate the experiment and data.