Atom-by-atom engineering of topological states of matter

by Prof. Cristiane Morais Smith (University of Utrecht)

Tuesday 12 Nov 2019, 16:00 → 17:30 Asia/Shanghai

TDLI Meeting Room 200

Abstract

Feynman’s original idea of using one quantum system that can be manipulated at will to simulate the behavior of another more complex one has flourished during the last decades in the field of cold atoms. More recently, this concept started to be developed in nanophotonics and in condensed matter. In this talk, I will discuss a few recent experiments, in which 2D electron lattices were engineered on the nanoscale. The first is the Lieb lattice [1, 2], and the second is a Sierpinski gasket [3], which has dimension D = 1.58. The realization of fractal lattices opens up the path to electronics in fractional dimensions. Finally, I will show how to realize topological states of matter using the same procedure. We investigate the robustness of the zero modes in a breathing Kagome lattice, which is the first experimental realization of a designed electronic higher-order topological insulator [4]. Then, we investigate the importance of the sample termination in determining the existence of topological edge modes in crystalline topological insulators. We focus on the breathing Kekule lattice, with two different types of termination [5]. In all cases, we observe an excellent agreement between the theoretical predictions and the experimental results.

[1] 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 realisation and characterisation of an electronic Lieb lattice”, Nature Physics 13, 672 (2017).

[2] M. R. Slot et al., “p-band engineering in artificial electronic lattices”, Phys. Rev. X 9, 011009 (2019).

[3] 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 electronic fractals”, Nature Physics 15,127(2019).

[4] 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: the dimerized Kagome lattice”, ArXiv: 1905.06053, in print in Nature Materials (2019).

[5] S. E. Freeney, J. J. van den Broeke, A. J. J. Harsveld van der Veen, I. Swart, and C. Morais Smith, “Edge dependent topology in Kekulé lattices”, submitted (2019).

Biography

Cristiane Morais Smith is professor of theoretical physics at the University of Utrecht, holding a chair in condensed matter. She is an expert on strongly correlated systems and topological insulators. She was awarded the Hamburg Dresselhaus Prize "for her outstanding contribution to the understanding of topological phases in two-dimensional atomic and electronic systems". Her group pioneered the development of a thermodynamic description of topological insulators and superconductors, as well as the use of a projected quantum electrodynamics (Pseudo QED) formulation to investigate topological phases driven by interactions. During the last few years, her group is playing an important role in the development of electronic quantum simulators and metamaterials in collaboration with an experimental group in Utrecht. 

International visibility, activities, prizes, scholarships etc.

• Professeur Boursier Grant of the Swiss National Science Foundation Switzerland, 2001 (1 million CH).
• VICI Grant, Dutch Research Council (NWO), The Netherlands, 2008.
• Special Visiting Professor Award, Science Without Borders, CNPq, Brazil, 2013-2016 (1.5 million Euro).
• High-End Foreign Experts (HEFE) team award, from the Chinese State Administration of Foreign Experts Affairs, Hangzhou, China, 2014 and 2015.
• Dresselhaus Prize (Senior), Hamburg University, Germany, 2016.
• Invited member of the Advisory Board (since 2018) and Fellow (since 2019) of the Tsung-Dao Lee Institute in Shanghai, China 
• Invited member of the Alexander von Humboldt Foundation for Research Fellowships and Prizes, Germany, since 2014.
• Invited member of the Wilczek Quantum Center, Shanghai, China, since 2014.
• Spotlight Prize of the Faculty of Sciences, Utrecht University (2015).
• Director of the ITP Master Program at Utrecht University (since 2016).
• Director of the Centre for Extreme Matter and Emergent Phenomena (since 2014).
• Member of the governing Board of the Dutch Research School in Theoretical Physics (since 2008)
• Member of the NWO Physics Table (since 2017)
• Editorial Board of European Physics Journal B (2011-2019)

Division

Condensed Matter