[{"type":"speech","title":"Evidence for quantum confinement in lognormal size distributed nanodiamonds","issued":{"date-parts":[["2008"]]},"author":[{"family":"Berg","given":"T."},{"family":"Marosits","given":"E."},{"family":"Maul","given":"J."},{"family":"Nagel","given":"P."},{"family":"Ott","given":"U."},{"family":"Schertz","given":"F."},{"family":"Schuppler","given":"S."},{"family":"Sudek","given":"C."},{"family":"Sch\u00f6nhense","given":"G."}],"note":"72.Jahrestagung der Deutschen Physikalischen Gesellschaft und DPG Fr\u00fchjahrstagung des Arbeitskreises Festk\u00f6rperphysik, Fachverband Oberfl\u00e4chenphysik, Berlin, 25.-29.Februar 2008 Verhandlungen der Deutschen Physikalischen Gesellschaft, R.6, B.43(2008) O 43.3","abstract":"Surface Science Division (O)\nTuesday\nCe surface alloys \u2014 \u2022Markus Klein1 , Christina Albers1 ,\nJuarez Da Silva3 , Kevin Beach2 , Fakher Assaad2 , and Friedrich\nReinert1 \u2014 1 Universit\u00a8t W\u00a8 rzburg, Experimentelle Physik II, Am\nHubland, 97074 W\u00a8rzburg, Germany \u2014 2 Universit\u00a8t W\u00a8rzburg, Theu\noretische Physik I, Am Hubland, 97074 W\u00a8 rzburg, Germany \u2014\n3 National Renewable Energy Laboratory, 1617 Cole Blvd., Golden,\nCO 80401, USA\nThe physical properties of Kondo systems are determined by interactions between localized f -states and conduction electrons. Of particular interest are low-dimensional systems as they can serve as elementary model systems. Due to its surface sensitivity angle-resolved\nphotoelectron spectroscopy (ARUPS) is an excellent tool to study directly the electronic structure of a two-dimensional Kondo system.\nThis requires highly ordered and ultra thin singlecrystalline \ufb01lms. We\nhave prepared singlecrystalline Ce surface-alloys by in situ deposition\nof Ce on noble metal surfaces. Our ARUPS results show a temperature\nand wave-vector dependent Kondo-resonance and other hybridization\ne\ufb00ects. We discuss our spectroscopic results with the help of data from\nisostructural La \ufb01lms, LDA+U, and DMFT calculations.\nO 43.2\nTue 18:30\nPoster F\nTemperature Dependence of the Single Particle Spectral\nFunction of the 2D Kondo Lattice Model using the Dynamical Cluster Approximation \u2014 \u2022Lee Martin and Fakher Assaad\n\u2014 Universit\u00a8t W\u00a8rzburg, Germany\nWe apply the dynamical cluster approximation, with a quantum Monte\nCarlo cluster solver using various cluster sizes, to the two-dimensional\nKondo lattice model to investigate the evolution of the conduction electron single particle spectral function as a function of temperature. In\nthe hole doped, paramagnetic metallic phase the problem contains two\nenergy scales: the Kondo temperature, TK , and the lower scale, the coherence temperature Tcoh . With decreasing temperature, moving from\nthe local moment to Kondo screened regime, we look for signatures of\nTK in the spectral function before \ufb01nally observing the formation of\nthe coherent heavy fermion state at and below Tcoh .\nO 43.3\nTue 18:30\nPoster F\nEvidence for quantum con\ufb01nement in lognormal size distributed nanodiamonds \u2014 \u2022Thomas Berg1 , Edit Marosits2 ,\n\u00a8\nStefan Schuppler3 , Christa Sudek2 , and Gerd Schonhense1 \u2014\nQuantum con\ufb01nement (QC) in semiconductor nanoparticles was discovered more than two decades ago and received increasing interest\nduring the recent years. In the case of nanodiamonds evidence for QC\nwas reported by [1], but the discussion on the extend of these e\ufb00ects\nin nanosized diamonds is still ongoing [2,3,4].\nWe report on NEXAFS-PEEM measurements of the Carbon K-edge\nof meteoritic nanodiamonds. The NEXAFS spectrum of this nanodiamond population shows a broadened and asymmetric exciton which\nwas assigned to the particles size distribution in recent publications\nbut a detailed explanation is still missing. We present quantitative\nanalysis of the modi\ufb01ed peak shape in respect to energy shifts of the\nexciton and the onset of the carbon K-edge caused by the well known\nsize distribution of this nanodiamond population as a consequence of\nQC. This project is supported by DFG (SCHO 341\/10-1).\n[1] Chang et al., Phys. Rev. Lett. 82, 5377 (1999) [2] Lley et al.,\nPhys. Rev. Lett. 84, 5679 (2000) [3] Pong et al., Phys. Rev. Lett. 84,\n5680 (2000) [4] Willey et al., Phys. Rev. Lett. 95, 113401 (2005)\nO 43.4\nTue 18:30\nPoster F\nSetup and Characterization of a Standing-Wave PEEM\nfor EUVL mask inspection \u2014 \u2022Jochen maul1 , Jingquan\nLin2 , Andreas Oelsner1 , Dima Valdaitsev1 , Nils Weber3 ,","kit-publication-id":"220071094"}]