Simulating quantum magnetism with quantum dot Arrays (Prof. Lieven Vandersypen)
Simulating quantum magnetism with quantum dot Arrays
- Date: Feb 4, 2020
- Time: 02:30 PM (Local Time Germany)
- Speaker: Prof. Lieven Vandersypen
- Delft University of Technology, Netherlands
- Location: Max Planck Institute of Quantum Optics
- Room: Herbert Walther Lecture Hall
Finally, the accessible observables include particle number, spin, spin correlations, addition energies and transport, complementing those of cold atom experiments. As a first illustration, we show the transition from Coulomb blockade to collective Coulomb blockade, the finite-size analogue of the metal to Mott insulator transition [1]. In a second experiment, we present evidence of Nagaoka ferromagnetism in a 2x2 quantum dot plaquette [2]. This is a form of magnetism that has not been observed before, highlighting the potential of quantum dots to provide new insights in Fermi-Hubbard physics. I will close with an overview and outlook of our recent work on silicon spin qubits [3-5].
[1] T. Hensgens, T. Fujita, L. Janssen, Xiao Li, C.J. van Diepen,
C. Reichl, W. Wegschneider, S. Das Sarma, L.M.K. Vandersypen, Quantum simulation of a Fermi-Hubbard model using a
semiconductor quantum dot array
Nature 548, 70–73 (2017)
[2] J.P. Dehollain, U. Mukhopadhyay, V.P. Michal, Y. Wang, B. Wunsch, C. Reichl, W. Wegscheider, M.S. Rudner, E. Demler, and L.M.K. Vandersypen, Nagaoka ferromagnetism observed in a quantum dot plaquette, Nature, in print (see arXiv:1904.05680)
[3] T.F. Watson, S.G.J. Philips, E. Kawakami, D.R. Ward, P. Scarlino, M. Veldhorst, D.E. Savage, M.G. Lagally, M. Friesen, S.N. Coppersmith, M.A. Eriksson, and L.M.K. Vandersypen, A programmable two-qubit quantum processor in silicon, Nature 555, 633-637 (2018)
[4] N. Samkharadze, G. Zheng, N. Kalhor, D. Brousse, A. Sammak, U.C. Mendes, A. Blais, G. Scappucci, and L.M.K. Vandersypen, Strong spin-photon coupling in silicon, Science 359, 1123-1127 (2018)
[5] X. Xue, T.F. Watson, J. Helsen, D.R. Ward, D.E. Savage, M.G. Lagally, S.N. Coppersmith, M.A. Eriksson, S. Wehner, and L.M.K. Vandersypen, Benchmarking Gate Fidelities in a Si/SiGe Two-Qubit Device, Phys. Rev. X 9, 021011 (2019)