Physics Colloquium: Atom by atom: Designing and realizing electronic quantum matter
Dr. Marlou Slot, NIST-Georgetown University
Abstract: Quantum simulators are a versatile tool to study the behavior of quantum matter in a controlled way. Elusive or complex quantum systems are simulated using accessible quantum systems that can be manipulated at will. While platforms based on, among others, ultracold atoms and photons are well-established, electronic platforms are currently being developed. A suitable electronic platform is provided by the 2D electron gas at specific metal surfaces. By atomic-scale patterning of the surface in a scanning tunneling microscope, the electrons can be molded into electronic lattices with nearly any geometry. The electronic structure of the realized lattice is investigated in-situ using scanning tunneling spectroscopy and wave-function mapping. In this talk, I will present CO molecules adsorbed on a Cu(111) surface as a highly-tunable electronic quantum simulator, in which the lattice geometry, the orbital degree of freedom, the dimension and the topology can be tailored [1-4].
 M. R. Slot, T. S. Gardenier, P. H. Jacobse, G. C. P. van Miert, S. N. Kempkes, S. J. M. Zevenhuizen, C. Morais Smith, D. Vanmaekelbergh and I. Swart, Experimental realization and characterization of an electronic Lieb lattice, Nature Physics 13, 672 (2017)
 S. N. Kempkes, M. R. Slot, S. E. Freeney, S. J. M. Zevenhuizen, D. Vanmaekelbergh, I. Swart and C. Morais Smith, Design and characterization of electrons in a fractal geometry, Nature Physics 15, 127 (2019)
 M. R. Slot, S. N. Kempkes, E. J. Knol, W. M. J. van Weerdenburg, D. Wegner, D. Vanmaekelbergh, A. A. Khajetoorians, C. Morais Smith and I. Swart, p-Band Engineering in Artificial Electronic Lattices, Physical Review X 9, 011009 (2019)
 S. N. Kempkes, M. R. Slot, J. J. van den Broeke, P. Capiod, W. A. Benalcazar, D. Vanmaekelbergh, D. Bercioux, I. Swart and C. Morais Smith, Robust zero-energy modes in an electronic higher-order topological insulator, Nature Materials 18, 1292 (2019)