Wenderoth, Martin

[["dc.bibliographiccitation.artnumber","115344"],["dc.bibliographiccitation.issue","11"],["dc.bibliographiccitation.journal","PHYSICAL REVIEW B"],["dc.bibliographiccitation.volume","77"],["dc.contributor.author","Loth, S."],["dc.contributor.author","Wenderoth, Martin"],["dc.contributor.author","Ulbrich, Rainer G."],["dc.date.accessioned","2018-11-07T11:18:01Z"],["dc.date.available","2018-11-07T11:18:01Z"],["dc.date.issued","2008"],["dc.description.abstract","The spatial distribution of the local density of states at Mn acceptors near the (110) surface of p-doped InAs is investigated by scanning tunneling microscopy. The shapes of the acceptor contrasts for different dopant depths under the surface are analyzed. Acceptors located within the first ten subsurface layers of the semiconductor show a lower symmetry than expected from theoretical predictions for the bulk acceptor wave function. They exhibit a (001) mirror asymmetry. The degree of asymmetry depends on the acceptor atoms' depths. The measured contrasts for acceptors buried below the tenth subsurface layer closely match the theoretically derived shape. Two effects are able to cause the observed symmetry reduction, i.e., the strain field of the surface relaxation and the tip-induced electric field. While both effects induce similar asymmetries, a comparison of their relative strengths indicates that surface-related strain is the dominant effect for Mn in InAs."],["dc.identifier.doi","10.1103/PhysRevB.77.115344"],["dc.identifier.isi","000254542800140"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/54949"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Physical Soc"],["dc.relation.issn","1098-0121"],["dc.title","Asymmetry of acceptor wave functions caused by surface-related strain and electric field in InAs"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","235318"],["dc.bibliographiccitation.issue","23"],["dc.bibliographiccitation.journal","PHYSICAL REVIEW B"],["dc.bibliographiccitation.volume","76"],["dc.contributor.author","Loth, S."],["dc.contributor.author","Wenderoth, Martin"],["dc.contributor.author","Ulbrich, Rainer G."],["dc.contributor.author","Malzer, S."],["dc.contributor.author","Doehler, G. H."],["dc.date.accessioned","2018-11-07T10:50:23Z"],["dc.date.available","2018-11-07T10:50:23Z"],["dc.date.issued","2007"],["dc.description.abstract","The electronic properties of shallow acceptors in p-doped GaAs{110} are investigated with scanning tunneling microscopy (STM) at low temperature. Shallow acceptors are known to exhibit distinct triangular contrasts in STM images for certain bias voltages. Spatially resolved I(V) spectroscopy is performed to identify their energetic origin and behavior. A crucial parameter-the scanning tunneling microscope tip's work function-is determined experimentally. The voltage dependent potential configuration and band bending situation are derived. Ways to validate the calculations with the experiment are discussed. Differential conductivity maps reveal that the triangular contrasts are only observed with a depletion layer present under the STM tip. The tunnel process leading to the anisotropic contrasts calls for electrons to tunnel through vacuum gap and a finite region in the semiconductor."],["dc.identifier.doi","10.1103/PhysRevB.76.235318"],["dc.identifier.isi","000251986500077"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/48635"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Physical Soc"],["dc.relation.issn","2469-9969"],["dc.relation.issn","2469-9950"],["dc.title","Connection of anisotropic conductivity to tip-induced space-charge layers in scanning tunneling spectroscopy of p-doped GaAs"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","193407"],["dc.bibliographiccitation.issue","19"],["dc.bibliographiccitation.journal","PHYSICAL REVIEW B"],["dc.bibliographiccitation.volume","76"],["dc.contributor.author","Homoth, J."],["dc.contributor.author","Wenderoth, Martin"],["dc.contributor.author","Engel, K. J."],["dc.contributor.author","Druga, T."],["dc.contributor.author","Loth, S."],["dc.contributor.author","Ulbrich, Rainer G."],["dc.date.accessioned","2018-11-07T10:57:28Z"],["dc.date.available","2018-11-07T10:57:28Z"],["dc.date.issued","2007"],["dc.description.abstract","We present scanning tunneling microscopy data on clean Ag(111) surfaces in UHV. Standing-wave patterns of the surface state are investigated to study the influence of a thermal step across the tunnel junction on constant current topographies. When constant current topographies are measured at bias voltages below 10 mV with temperature differences of more than a few kelvins between tip and sample, the apparent corrugation is drastically increased. Constant current topographies at low bias voltages and finite temperature differences do not reveal the true local density of states of the surface. The apparent corrugation is caused by a spatial varying thermovoltage superimposed to the bias voltage while scanning the sample's local density of states. With the help of scanning tunneling potentiometry, the correct local density of states of the sample can be reconstructed."],["dc.identifier.doi","10.1103/PhysRevB.76.193407"],["dc.identifier.isi","000251326800032"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/50259"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Physical Soc"],["dc.relation.issn","1098-0121"],["dc.title","Reconstruction of the local density of states in Ag(111) surfaces using scanning tunneling potentiometry"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","3538"],["dc.bibliographiccitation.issue","9"],["dc.bibliographiccitation.journal","Nano Letters"],["dc.bibliographiccitation.lastpage","3542"],["dc.bibliographiccitation.volume","11"],["dc.contributor.author","Teichmann, K."],["dc.contributor.author","Wenderoth, Martin"],["dc.contributor.author","Loth, S."],["dc.contributor.author","Garleff, J. K."],["dc.contributor.author","Wijnheijmer, A. P."],["dc.contributor.author","Koenraad, P. M."],["dc.contributor.author","Ulbrich, Rainer G."],["dc.date.accessioned","2018-11-07T08:52:14Z"],["dc.date.available","2018-11-07T08:52:14Z"],["dc.date.issued","2011"],["dc.description.abstract","In gated semiconductor devices, the space charge layer that is located under the gate electrode acts as the functional element. With increasing gate voltage, the microscopic process forming this space charge layer involves the subsequent ionization or electron capture of individual dopants within the semiconductor. In this Letter, a scanning tunneling microscope tip is used as a movable gate above the (110) surface of n-doped GaAs. We study the build-up process of the space charge region considering donors and visualize the charge states of individual and multi donor systems. The charge configuration of single donors is determined by the position of the tip and the applied gate voltage. In contrast, a two donor system with interdonor distances smaller than 10 nm shows a more complex behavior. The electrostatic interaction between the donors in combination with the modification of their electronic properties close to the surface results in ionization gaps and bistable charge switching behavior."],["dc.identifier.doi","10.1021/nl201024b"],["dc.identifier.isi","000294790200005"],["dc.identifier.pmid","21842882"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/22117"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Chemical Soc"],["dc.relation.issn","1530-6984"],["dc.title","Bistable Charge Configuration of Donor Systems near the GaAs(110) Surfaces"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","076103"],["dc.bibliographiccitation.issue","7"],["dc.bibliographiccitation.journal","Physical Review Letters"],["dc.bibliographiccitation.volume","101"],["dc.contributor.author","Teichmann, K."],["dc.contributor.author","Wenderoth, Martin"],["dc.contributor.author","Loth, S."],["dc.contributor.author","Ulbrich, Rainer G."],["dc.contributor.author","Garleff, J. K."],["dc.contributor.author","Wijnheijmer, A. P."],["dc.contributor.author","Koenraad, P. M."],["dc.date.accessioned","2018-11-07T11:12:09Z"],["dc.date.available","2018-11-07T11:12:09Z"],["dc.date.issued","2008"],["dc.description.abstract","The charge state of individually addressable impurities in semiconductor material was manipulated with a scanning tunneling microscope. The manipulation was fully controlled by the position of the tip and the voltage applied between tip and sample. The experiments were performed at low temperature on the {110} surface of silicon doped GaAs. Silicon donors up to 1 nm below the surface can be reversibly switched between their neutral and ionized state by the local potential induced by the tip. By using ultrasharp tips, the switching process occurs close enough to the impurity to be observed as a sharp circular feature surrounding the donor. By utilizing the controlled manipulation, we were able to map the Coulomb potential of a single donor at the semiconductor-vacuum interface."],["dc.identifier.doi","10.1103/PhysRevLett.101.076103"],["dc.identifier.isi","000258473800048"],["dc.identifier.pmid","18764558"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/53600"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Physical Soc"],["dc.relation.issn","0031-9007"],["dc.title","Controlled charge switching on a single donor with a scanning tunneling microscope"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2193"],["dc.bibliographiccitation.issue","3B"],["dc.bibliographiccitation.journal","JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS"],["dc.bibliographiccitation.lastpage","2196"],["dc.bibliographiccitation.volume","45"],["dc.contributor.author","Loth, S."],["dc.contributor.author","Wenderoth, Martin"],["dc.contributor.author","Winking, L."],["dc.contributor.author","Ulbrich, Rainer G."],["dc.contributor.author","Malzer, S."],["dc.contributor.author","Dohler, G. H."],["dc.date.accessioned","2018-11-07T10:13:00Z"],["dc.date.available","2018-11-07T10:13:00Z"],["dc.date.issued","2006"],["dc.description.abstract","Scanning tunneling spectroscopy (STS) at 8 K is used to study single shallow acceptors embedded near {110}-surfaces ill gallium arsenide (GaAs). At appropriate bias voltages the circularly symmetric contrast normally observed for charged defects evolves into a pronounced triangular shaped protrusion. Comparing dopants at different depths under the surface, we find a linear shift of the associated conductivity maximum along (112) directions. Comparative Studies of Carbon and Zinc acceptors in a modulation-doped heterostructure reveal that both dopants act similarly. The experimental findings Suggest that the highly anisotropic features induced by acceptors resemble a bulk property of the GaAs crystal prominently demonstrating its Ziricblende symmetry."],["dc.identifier.doi","10.1143/JJAP.45.2193"],["dc.identifier.isi","000236624100073"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/40346"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Inst Pure Applied Physics"],["dc.publisher.place","Tokyo"],["dc.relation.conference","13th International Conference on Scanning Tunneling Microscopy, Spectroscopy and Related Technique held in Conjunction with the 13th International Colloquium on Scanning Probe Microscopy"],["dc.relation.eventlocation","Sapporo, JAPAN"],["dc.relation.issn","0021-4922"],["dc.title","Depth resolved scanning tunneling spectroscopy of shallow acceptors in gallium arsenide"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","125310"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","PHYSICAL REVIEW B"],["dc.bibliographiccitation.volume","84"],["dc.contributor.author","Wijnheijmer, A. P."],["dc.contributor.author","Garleff, J. K."],["dc.contributor.author","Teichmann, K."],["dc.contributor.author","Wenderoth, Martin"],["dc.contributor.author","Loth, S."],["dc.contributor.author","Koenraad, P. M."],["dc.date.accessioned","2018-11-07T08:51:46Z"],["dc.date.available","2018-11-07T08:51:46Z"],["dc.date.issued","2011"],["dc.description.abstract","We present a comprehensive scanning tunneling microscopy and spectroscopy study of individual Si dopants in GaAs. We explain all the spectroscopic peaks and their voltage dependence in the band gap and in the conduction band. We observe both the filled and empty donor state. Donors close to the surface, which have an enhanced binding energy, show a second ionization ring, corresponding to the negatively charged donor D-. The observation of all predicted features at the expected spectral position and with the expected voltage-distance dependence confirms their correct identification and the semiquantitative analyses of their energetic positions."],["dc.description.sponsorship","NAMASTE; [DFG-SFB 602]; [DFG-SPP 1285]"],["dc.identifier.doi","10.1103/PhysRevB.84.125310"],["dc.identifier.isi","000294777800010"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/22014"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Physical Soc"],["dc.relation.issn","1098-0121"],["dc.title","Single Si dopants in GaAs studied by scanning tunneling microscopy and spectroscopy"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","166101"],["dc.bibliographiccitation.issue","16"],["dc.bibliographiccitation.journal","Physical Review Letters"],["dc.bibliographiccitation.volume","102"],["dc.contributor.author","Wijnheijmer, A. P."],["dc.contributor.author","Garleff, J. K."],["dc.contributor.author","Teichmann, K."],["dc.contributor.author","Wenderoth, Martin"],["dc.contributor.author","Loth, S."],["dc.contributor.author","Ulbrich, Rainer G."],["dc.contributor.author","Maksym, P. A."],["dc.contributor.author","Roy, M."],["dc.contributor.author","Koenraad, P. M."],["dc.date.accessioned","2018-11-07T08:30:42Z"],["dc.date.available","2018-11-07T08:30:42Z"],["dc.date.issued","2009"],["dc.description.abstract","We measured the ionization threshold voltage of individual impurities close to a semiconductor-vacuum interface, where we use the STM tip to ionize individual donors. We observe a reversed order of ionization with depth below the surface, which proves that the binding energy is enhanced towards the surface. This is in contrast to the predicted reduction for a Coulombic impurity in the effective mass approach. We can estimate the binding energy from the ionization threshold and show experimentally that in the case of silicon doped gallium arsenide the binding energy gradually increases over the last 1.2 nm below the (110) surface."],["dc.description.sponsorship","NAMASTE [214499]; STW-VICI [6631]; DFG-SFB [602]; DFG-SPP [1285]"],["dc.identifier.doi","10.1103/PhysRevLett.102.166101"],["dc.identifier.isi","000265479300042"],["dc.identifier.pmid","19518726"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/16951"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Physical Soc"],["dc.relation.issn","0031-9007"],["dc.title","Enhanced Donor Binding Energy Close to a Semiconductor Surface"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","066403"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Physical Review Letters"],["dc.bibliographiccitation.volume","96"],["dc.contributor.author","Loth, S."],["dc.contributor.author","Wenderoth, Martin"],["dc.contributor.author","Winking, L."],["dc.contributor.author","Ulbrich, Rainer G."],["dc.contributor.author","Malzer, S."],["dc.contributor.author","Dohler, G. H."],["dc.date.accessioned","2018-11-07T10:18:01Z"],["dc.date.available","2018-11-07T10:18:01Z"],["dc.date.issued","2006"],["dc.description.abstract","Tunneling transport through the depletion layer under a GaAs {110} surface is studied with a low temperature scanning tunneling microscope (STM). The observed negative differential conductivity is due to a resonant enhancement of the tunneling probability through the depletion layer mediated by individual shallow acceptors. The STM experiment probes, for appropriate bias voltages, evanescent states in the GaAs band gap. Energetically and spatially resolved spectra show that the pronounced anisotropic contrast pattern of shallow acceptors occurs exclusively for this specific transport channel. Our findings suggest that the complex band structure causes the observed anisotropies connected with the zinc blende symmetry."],["dc.identifier.doi","10.1103/PhysRevLett.96.066403"],["dc.identifier.isi","000235394100057"],["dc.identifier.pmid","16606021"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/41346"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","American Physical Soc"],["dc.relation.issn","0031-9007"],["dc.title","Probing semiconductor gap states with resonant tunneling"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]