@article{13538, author = {{Riefer, A. and Sanna, S. and Schmidt, Wolf Gero}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{12}}, title = {{{Polarization-dependent methanol adsorption on lithium niobate Z-cut surfaces}}}, doi = {{10.1103/physrevb.86.125410}}, volume = {{86}}, year = {{2012}}, } @article{13820, author = {{Schmidt, Wolf Gero and Wippermann, S. and Sanna, S. and Babilon, M. and Vollmers, N. J. and Gerstmann, Uwe}}, issn = {{0370-1972}}, journal = {{physica status solidi (b)}}, number = {{2}}, pages = {{343--359}}, title = {{{In-Si(111)(4 × 1)/(8 × 2) nanowires: Electron transport, entropy, and metal-insulator transition}}}, doi = {{10.1002/pssb.201100457}}, volume = {{249}}, year = {{2012}}, } @article{4136, abstract = {{Results of atomistic simulations aimed at understanding precipitation of the highly attractive wide band gap semiconductor material silicon carbide in silicon are presented. The study involves a systematic investigation of intrinsic and carbon-related defects as well as defect combinations and defect migration by both, quantummechanical first-principles as well as empirical potential methods. Comparing formation and activation energies, ground-state structures of defects and defect combinations as well as energetically favorable agglomeration of defects are predicted. Moreover, accurate ab initio calculations unveil limitations of the analytical method based on a Tersoff-like bond order potential. A work-around is proposed in order to subsequently apply the highly efficient technique on large structures not accessible by first-principles methods. The outcome of both types of simulation provides a basic microscopic understanding of defect formation and structural evolution particularly at non-equilibrium conditions strongly deviated from the ground state as commonly found in SiC growth processes. A possible precipitation mechanism, which conforms well to experimental findings and clarifies contradictory views present in the literature is outlined.}}, author = {{Zirkelbach, F. and Stritzker, B. and Nordlund, K. and Schmidt, Wolf Gero and Rauls, E. and Lindner, Jörg K. N.}}, issn = {{1862-6351}}, journal = {{physica status solidi (c)}}, number = {{10-11}}, pages = {{1968--1973}}, publisher = {{Wiley}}, title = {{{First-principles and empirical potential simulation study of intrinsic and carbon-related defects in silicon}}}, doi = {{10.1002/pssc.201200198}}, volume = {{9}}, year = {{2012}}, } @article{13565, author = {{Müllegger, Stefan and Schöfberger, Wolfgang and Rashidi, Mohammad and Lengauer, Thomas and Klappenberger, Florian and Diller, Katharina and Kara, Kamuran and Barth, Johannes V. and Rauls, Eva and Schmidt, Wolf Gero and Koch, Reinhold}}, issn = {{1936-0851}}, journal = {{ACS Nano}}, number = {{8}}, pages = {{6480--6486}}, title = {{{Preserving Charge and Oxidation State of Au(III) Ions in an Agent-Functionalized Nanocrystal Model System}}}, doi = {{10.1021/nn201708c}}, volume = {{5}}, year = {{2011}}, } @article{13566, author = {{Hoehne, Felix and Lu, Jinming and Stegner, Andre R. and Stutzmann, Martin and Brandt, Martin S. and Rohrmüller, Martin and Schmidt, Wolf Gero and Gerstmann, Uwe}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, number = {{19}}, title = {{{Electrically Detected Electron-Spin-Echo Envelope Modulation: A Highly Sensitive Technique for Resolving Complex Interface Structures}}}, doi = {{10.1103/physrevlett.106.196101}}, volume = {{106}}, year = {{2011}}, } @article{13568, author = {{Mietze, C. and Landmann, M. and Rauls, E. and Machhadani, H. and Sakr, S. and Tchernycheva, M. and Julien, F. H. and Schmidt, Wolf Gero and Lischka, K. and As, Donat Josef}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{19}}, title = {{{Band offsets in cubic GaN/AlN superlattices}}}, doi = {{10.1103/physrevb.83.195301}}, volume = {{83}}, year = {{2011}}, } @article{13570, author = {{Müllegger, S. and Rashidi, M. and Lengauer, T. and Rauls, E. and Schmidt, Wolf Gero and Knör, G. and Schöfberger, W. and Koch, R.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{16}}, title = {{{Asymmetric saddling of single porphyrin molecules on Au(111)}}}, doi = {{10.1103/physrevb.83.165416}}, volume = {{83}}, year = {{2011}}, } @article{13567, author = {{Konopka, A. and Greulich-Weber, S. and Dierolf, V. and Jiang, H.X. and Gerstmann, Uwe and Rauls, E. and Sanna, S. and Schmidt, Wolf Gero}}, issn = {{0925-3467}}, journal = {{Optical Materials}}, pages = {{1041--1044}}, title = {{{Microscopic structure and energy transfer of vacancy-related defect pairs with Erbium in wide-gap semiconductors}}}, doi = {{10.1016/j.optmat.2010.12.005}}, volume = {{33}}, year = {{2011}}, } @article{13571, author = {{Thierfelder, C. and Witte, M. and Blankenburg, S. and Rauls, E. and Schmidt, Wolf Gero}}, issn = {{0039-6028}}, journal = {{Surface Science}}, pages = {{746--749}}, title = {{{Methane adsorption on graphene from first principles including dispersion interaction}}}, doi = {{10.1016/j.susc.2011.01.012}}, volume = {{605}}, year = {{2011}}, } @article{13569, author = {{Favero, P.P. and Ferraz, A.C. and Schmidt, Wolf Gero and Miotto, R.}}, issn = {{0039-6028}}, journal = {{Surface Science}}, pages = {{824--830}}, title = {{{Driving forces for the adsorption of cyclopentene on InP(001)}}}, doi = {{10.1016/j.susc.2011.01.027}}, volume = {{605}}, year = {{2011}}, } @article{13563, author = {{Schmidt, Wolf Gero and Babilon, M. and Thierfelder, C. and Sanna, S. and Wippermann, S.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{11}}, title = {{{Influence of Na adsorption on the quantum conductance and metal-insulator transition of the In-Si(111)(4×1)–(8×2) nanowire array}}}, doi = {{10.1103/physrevb.84.115416}}, volume = {{84}}, year = {{2011}}, } @article{13561, author = {{Berth, Gerhard and Hahn, Wjatscheslaw and Wiedemeier, Volker and Zrenner, Artur and Sanna, Simone and Schmidt, Wolf Gero}}, issn = {{0015-0193}}, journal = {{Ferroelectrics}}, pages = {{44--48}}, title = {{{Imaging of the Ferroelectric Domain Structures by Confocal Raman Spectroscopy}}}, doi = {{10.1080/00150193.2011.594774}}, volume = {{420}}, year = {{2011}}, } @article{13564, author = {{dos Santos, L. S. and Schmidt, Wolf Gero and Rauls, E.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{11}}, title = {{{Group-VII point defects in ZnSe}}}, doi = {{10.1103/physrevb.84.115201}}, volume = {{84}}, year = {{2011}}, } @article{13825, author = {{Sanna, S. and Thierfelder, C. and Wippermann, S. and Sinha, T. P. and Schmidt, Wolf Gero}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{5}}, title = {{{Barium titanate ground- and excited-state properties from first-principles calculations}}}, doi = {{10.1103/physrevb.83.054112}}, volume = {{83}}, year = {{2011}}, } @article{13823, author = {{Sanna, S. and Berth, Gerhard and Hahn, W. and Widhalm, A. and Zrenner, Artur and Schmidt, Wolf Gero}}, issn = {{0885-3010}}, journal = {{IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control}}, number = {{9}}, pages = {{1751--1756}}, title = {{{Vibrational properties of the LiNbO3 z-surfaces}}}, doi = {{10.1109/tuffc.2011.2012}}, volume = {{58}}, year = {{2011}}, } @article{13824, author = {{Zirkelbach, F. and Stritzker, B. and Nordlund, K. and Lindner, J. K. N. and Schmidt, Wolf Gero and Rauls, E.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{6}}, title = {{{Combined ab initio and classical potential simulation study on silicon carbide precipitation in silicon}}}, doi = {{10.1103/physrevb.84.064126}}, volume = {{84}}, year = {{2011}}, } @article{4543, abstract = {{The vibrational properties of the LiNbO3 (0001) surfaces have been investigated both from first principles and with Raman spectroscopy measurements. Firstly, the phonon modes of bulk and of the (0001) surface are calculated by means of the density functional theory. Our calculations reveal the existence of localised vibrational modes both at the positive and at the negative surface. The surface vibrations are found at energies above and within the bulk bands. Phonon modes localised at the positive and at the negative surface differ substantially. In a second step, the Raman spectra of LiNbO3 bulk and of the two surfaces have been measured. Raman spectroscopy is shown to be sensitive to differences between bulk and surface and between positive and negative surface. The calculated and measured frequencies are in agreement within the error of the method.}}, author = {{Sanna, S. and Berth, Gerhard and Hahn, W. and Widhalm, A. and Zrenner, Artur and Schmidt, Wolf Gero}}, issn = {{0015-0193}}, journal = {{Ferroelectrics}}, number = {{1}}, pages = {{1--8}}, publisher = {{Informa UK Limited}}, title = {{{Localised Phonon Modes at LiNbO3(0001) Surfaces}}}, doi = {{10.1080/00150193.2011.594396}}, volume = {{419}}, year = {{2011}}, } @article{13581, author = {{Wippermann, S. and Schmidt, Wolf Gero and Bechstedt, F. and Chandola, S. and Hinrichs, K. and Gensch, M. and Esser, N. and Fleischer, K. and McGilp, J. F.}}, issn = {{1862-6351}}, journal = {{physica status solidi (c)}}, number = {{2}}, pages = {{133--136}}, title = {{{Optical anisotropy of Si(111)-(4 × 1)/(8 × 2)-In nanowires calculated fromfirst-principles}}}, doi = {{10.1002/pssc.200982413}}, volume = {{7}}, year = {{2010}}, } @article{13573, abstract = {{Given the vast range of lithium niobate (LiNbO3) applications, the knowledge about its electronic and optical properties is surprisingly limited. The direct band gap of 3.7 eV for the ferroelectric phase – frequently cited in the literature – is concluded from optical experiments. Recent theoretical investigations show that the electronic band‐structure and optical properties are very sensitive to quasiparticle and electron‐hole attraction effects, which were included using the GW approximation for the electron self‐energy and the Bethe‐Salpeter equation respectively, both based on a model screening function. The calculated fundamental gap was found to be at least 1 eV larger than the experimental value. To resolve this discrepancy we performed first‐principles GW calculations for lithium niobate using the full‐potential linearized augmented plane‐wave (FLAPW) method. Thereby we use the parameter‐free random phase approximation for a realistic description of the nonlocal and energydependent screening. This leads to a band gap of about 4.7 (4.2) eV for ferro(para)‐electric lithium niobate.}}, author = {{Thierfelder, Christian and Sanna, Simone and Schindlmayr, Arno and Schmidt, Wolf Gero}}, issn = {{1610-1642}}, journal = {{Physica Status Solidi C}}, location = {{Weimar}}, number = {{2}}, pages = {{362--365}}, publisher = {{Wiley-VCH}}, title = {{{Do we know the band gap of lithium niobate?}}}, doi = {{10.1002/pssc.200982473}}, volume = {{7}}, year = {{2010}}, } @article{13574, author = {{Gerstmann, Uwe and Rohrmüller, M. and Mauri, F. and Schmidt, Wolf Gero}}, issn = {{1862-6351}}, journal = {{physica status solidi (c)}}, number = {{2}}, pages = {{157--160}}, title = {{{Ab initiog-tensor calculation for paramagnetic surface states: hydrogen adsorption at Si surfaces}}}, doi = {{10.1002/pssc.200982462}}, volume = {{7}}, year = {{2010}}, }