主讲人：Harold J.W. Zandvliet，University of Twente
Abstract:Germanene, the germanium analogue of graphene, is in many aspects very similar to graphene, but in contrast to the planar graphene lattice, the germanene honeycomb lattice is slightly buckled and composed of two vertically displaced sub-lattices . Frist principles total energy calculations have revealed that freestanding germanene is a two-dimensional Dirac fermion system, i.e. the electrons behave as massless relativistic particles that are described by the Dirac equation, i.e. the relativistic variant of the Schr?dinger equation. Recently, it has been shown that germanene can be synthesized on various substrates, including MoS2 and Ge2Pt [2-4]. As predicted germanene’s honeycomb lattice is indeed buckled and the experimentally measured density of states exhibits a V-shape, which is one of the hall marks of a two-dimensional Dirac system. Spatial maps of the Dirac point of germanene synthesized on MoS2 reveal the presence of charge puddles, which are induced by charged defects of the underlying substrate.
Biography: Harold J.W. Zandvliet (July 22th 1963, Haarlem) earned an ir (ingenieur) degree in Applied Physics with the highest distinction (met lof/cum laude) at the Technische Hogeschool Twente in June 1986. In 1990 he obtained his PhD in the field of condensed matter physics at the University of Twente under the supervision of Profs. Arend van Silfhout and Hans Sparnaay. He then joined the Philips Research (Natlab) in Eindhoven, where he worked as a permanent scientific staff member in the department headed by Dr. Andries Miedema. At Philips he was member of a small team that has built one of the first high-temperature scanning tunnelling microscopes in the world. In April 1992 he returned to the University of Twente as an assistant, and later associate professor in the Solid State Physics group headed by Prof. Bene Poelsema. In July 2002 he obtained a VIDI vernieuwingsimpuls grant for a proposal entitled “Molecular Electronics”. Since June 2005 he is a full professor of the Faculty of Science and Technology. Harold Zandvliet was a member of the editorial board of Journal of Physics Condensed Matter from January 2007 till December 2016. From January 2010 till December 2016 he served as chief Editor of the Surface, Interface and Atomic-Scale Science section of Journal of Physics Condensed Matter. He is also member of the advisory editorial board of Applied Surface Science. Harold Zandvliet is the principal investigator and coordinator of two national research programs: The singular physics of 1D electrons (2011-2016) and Two-dimensional semiconductor crystals (2015-2020). Harold Zandvliet is an elected Fellow of the IOP (Institute of Physics) and recipient of the APS outstanding referee award.