Free-radical gases on two-dimensional transition-metal disulfides (XS₂, X = Mo/W): robust half-metallicity for efficient nitrogen oxide sensors

• Chunmei Zhang,
• Yalong Jiao,
• Fengxian Ma,
• Sri Kasi Matta,
• Steven Bottle and
• Aijun Du

Beilstein J. Nanotechnol. 2018, 9, 1641–1646, doi:10.3762/bjnano.9.156

• . The binding position and adsorption energy are analyzed in detail. In terms of the projected density of states (PDOS) and orbital contribution, our results offer a deep insight into the Fermi-level pinning mechanism. In addition, we expand the calculations to other 2D layered materials including GaS

• spin-unpaired electrons are localized on the NO and NO2 molecule (insets of Figure 2b,c,e,f) [30]. The concept of Fermi-level pinning is usually used in the metal–semiconductor interface region. Zhou et al. [28] Introduced the concept of Fermi-level pinning into the field of gas/2D nanomaterial systems

• . However, they failed to point out the spin-polarized Fermi-level pinning in gas/2D nanomaterial system. Based on this, we take the single-layer WS2 as an example to elucidate the different Fermi-level pinning processes of adsorption of NO and NO2. The spin orbital-resolved band structures are simulated

Disorder-induced suppression of the zero-bias conductance peak splitting in topological superconducting nanowires

• Jun-Tong Ren,
• Hai-Feng Lü,
• Sha-Sha Ke,
• Yong Guo and
• Huai-Wu Zhang

Beilstein J. Nanotechnol. 2018, 9, 1358–1369, doi:10.3762/bjnano.9.128

• ], among which some possible reasons have been proposed, such as the combining effect of high temperature and multisubband occupancy in a Coulomb-blocked nanowire where the non-topological low-energy Andreev bound states and MBSs simultaneously exist [53], the zero-energy pinning effect induced by the

Field-controlled ultrafast magnetization dynamics in two-dimensional nanoscale ferromagnetic antidot arrays

• Anulekha De,
• Sucheta Mondal,
• Sourav Sahoo,
• Saswati Barman,
• Yoshichika Otani,
• Rajib Kumar Mitra and
• Anjan Barman

Beilstein J. Nanotechnol. 2018, 9, 1123–1134, doi:10.3762/bjnano.9.104

• full range of 0° to 90°) for this type of complex magnonic crystal have not been studied earlier. Also the sharp corners of the triangular holes of the high density antidot lattice and the complicated lattice structure create inhomogeneous internal magnetic fields due to the effective pinning centres

Inelastic electron tunneling spectroscopy of difurylethene-based photochromic single-molecule junctions

• Youngsang Kim,
• Safa G. Bahoosh,
• Dmytro Sysoiev,
• Thomas Huhn,
• Fabian Pauly and
• Elke Scheer

Beilstein J. Nanotechnol. 2017, 8, 2606–2614, doi:10.3762/bjnano.8.261

• located around 0.2 eV below EF. The pinning of the HOMO level at EF for the closed form may lead to enhanced uncertainties with regard to the description of the level alignment in this molecular state with its extended conjugated electron system as compared to the open form with its interrupted π system

Substrate and Mg doping effects in GaAs nanowires

• Perumal Kannappan,
• Nabiha Ben Sedrine,
• Jennifer P. Teixeira,
• Maria R. Soares,
• Bruno P. Falcão,
• Maria R. Correia,
• Nestor Cifuentes,
• Emilson R. Viana,
• Marcus V. B. Moreira,
• Geraldo M. Ribeiro,
• Alfredo G. de Oliveira,
• Juan C. González and
• Joaquim P. Leitão

Beilstein J. Nanotechnol. 2017, 8, 2126–2138, doi:10.3762/bjnano.8.212

• surface charge traps that induce a pinning of the Fermi level at the surface, especially for diameters below 100 nm [68]. However, if we compare the diameter of the three studied nanowires #1, #2 and #3, which were 190, 187 and 179 nm, respectively, the effect of surface scattering should be similar

Magnetic properties of optimized cobalt nanospheres grown by focused electron beam induced deposition (FEBID) on cantilever tips

• Soraya Sangiao,
• César Magén,
• Darius Mofakhami,
• Grégoire de Loubens and
• José María De Teresa

Beilstein J. Nanotechnol. 2017, 8, 2106–2115, doi:10.3762/bjnano.8.210

• -vortex-lattice pinning [17]; as well as (d) three-dimensional nanowires for magnetic domain-wall studies [18][19] and for remote magnetomechanical actuation [20], quantum dots for magnetic storage [21] and catalytic purposes [22], polygonal shapes for micromagnetic studies [23][24] and spin-ice

• investigations [25], nanoconstrictions and nanocontacts for domain-wall pinning [26] and Andreev reflection studies [27]. The growth of such numerous types of 2D and 3D magnetic nanostructures has been possible thanks to the main virtues of the FEBID technique such as: arbitrary design of the beam scan path [28

Adsorbate-driven cooling of carbene-based molecular junctions

• Giuseppe Foti and
• Héctor Vázquez

Beilstein J. Nanotechnol. 2017, 8, 2060–2068, doi:10.3762/bjnano.8.206

• a different bias dependence. While adsorbate states are strongly pinned to the chemical potential of the left electrode, NHC states do not clearly follow the potential of either electrode. Figure 3 shows the pinning of the molecular HOMO and LUMO and of the states of the adsorbate. The figure tracks

• matches that of the CA junction. This ensures that other effects introduced by the adsorbate (e.g., hybridization) are excluded. We note that the pinning behavior of the LUMO in the C and CA junctions is slightly different and therefore the LUMO peaks are matched at each applied voltage. Figure 5 shows

Air–water interface of submerged superhydrophobic surfaces imaged by atomic force microscopy

• Markus Moosmann,
• Thomas Schimmel,
• Wilhelm Barthlott and
• Matthias Mail

Beilstein J. Nanotechnol. 2017, 8, 1671–1679, doi:10.3762/bjnano.8.167

• scanning. In particular, the question arose: what happens when the normal force is increased? Two possible options are presented in Figure 6. In case of a “pinning” situation of the air–water interface to the tip (schematically illustrated in image 1 in Figure 6a), an increase of the normal force will pull

• deflection of the cantilever is detected. With the cantilever calibrated, the deflection is automatically translated into the corresponding force. Considering that not only the cantilever but also the air–water interface acts according to Hooke’s law, we expect the pinning behavior to be relevant (as

• sample. Here the normal force applied is maximal. As the AFM tip is retracted, the force on the tip decreases. At point 2, the air–water interface is at equilibrium and no resulting force can be detected. Beyond this point, the further retraction forces the cantilever to buckle due to pinning, and the

Adsorption and electronic properties of pentacene on thin dielectric decoupling layers

• Sebastian Koslowski,
• Daniel Rosenblatt,
• Alexander Kabakchiev,
• Klaus Kuhnke,
• Klaus Kern and
• Uta Schlickum

Beilstein J. Nanotechnol. 2017, 8, 1388–1395, doi:10.3762/bjnano.8.140

• to 0 reveals the vacuum-level pinning of Ea, which suggests a weak coupling of this orbital to the substrate. On the other hand, Ei decreases with increasing work function, with a slope SHOMO = −1.22 ± 0.28. In this case, the value of SHOMO is close to −1 (within less than a standard deviation of −1

• pinning for HOMO and LUMO [17] is not limited to molecules adsorbed onto bare metals, but is also valid for single molecules on metals covered with a thin decoupling layer having homogeneous properties. An exception is found for the HOMO on h-BN where the intrinsic dipole moment of the molecule within the

Measuring adhesion on rough surfaces using atomic force microscopy with a liquid probe

• Juan V. Escobar,
• Cristina Garza and
• Rolando Castillo

Beilstein J. Nanotechnol. 2017, 8, 813–825, doi:10.3762/bjnano.8.84

• , we obtain Fadh/peak = 14.9 pN (r = 0.992). This value is larger than the Fadh/peak obtained for the glass sphere because wetting is probably playing a significant role; the grating is not supersolvophobic for mercury. Interestingly, this number is close to the smallest values of the pinning forces

• smallest ones found for the contact between nanotubes and liquids [35]. It could be possible that the unit of force that we measure corresponds to a single pinning point of the contact line. This suggests that the method we have reported here can give useful information about fundamental wetting properties

Impact of contact resistance on the electrical properties of MoS₂ transistors at practical operating temperatures

• Filippo Giannazzo,
• Gabriele Fisichella,
• Aurora Piazza,
• Salvatore Di Franco,
• Giuseppe Greco,
• Simonpietro Agnello and
• Fabrizio Roccaforte

Beilstein J. Nanotechnol. 2017, 8, 254–263, doi:10.3762/bjnano.8.28

• Fermi level pinning close to the conduction band of MoS2 [5], resulting in a Schottky barrier height (SBH) for electrons typically ranging from 0.1 to 0.3 eV. The origin of this Fermi level pinning is currently a matter of investigation and a crucial role seems to be played by nanoscale defects

Thickness-modulated tungsten–carbon superconducting nanostructures grown by focused ion beam induced deposition for vortex pinning up to high magnetic fields

• Ismael García Serrano,
• Javier Sesé,
• Isabel Guillamón,
• Hermann Suderow,
• Sebastián Vieira,
• Manuel Ricardo Ibarra and
• José María De Teresa

Beilstein J. Nanotechnol. 2016, 7, 1698–1708, doi:10.3762/bjnano.7.162

• Materiales de Aragón (ICMA), CSIC - Universidad de Zaragoza, 50009 Zaragoza, Spain 10.3762/bjnano.7.162 Abstract We report efficient vortex pinning in thickness-modulated tungsten–carbon-based (W–C) nanostructures grown by focused ion beam induced deposition (FIBID). By using FIBID, W–C superconducting

• films have been created with thickness modulation properties exhibiting periodicity from 60 to 140 nm, leading to a strong pinning potential for the vortex lattice. This produces local minima in the resistivity up to high magnetic fields (2.2 T) in a broad temperature range due to commensurability

• effects between the pinning potential and the vortex lattice. The results show that the combination of single-step FIBID fabrication of superconducting nanostructures with built-in artificial pinning landscapes and the small intrinsic random pinning potential of this material produces strong periodic

Surface roughness rather than surface chemistry essentially affects insect adhesion

• Matt W. England,
• Tomoya Sato,
• Makoto Yagihashi,
• Atsushi Hozumi,
• Stanislav N. Gorb and
• Elena V. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1471–1479, doi:10.3762/bjnano.7.139

• to that observed in air. The oil-covered hairy pads on the feet of the beetle show a pinning effect, which retains air bubbles, and capillary attachment is produced by bubbles in contact with the hydrophobic substrate. Additionally, the liquid bridges of the pad between the foot and the substrate

• surface could move, without pinning, more smoothly than they could on a smooth FAS17 surface (Δθ = 13°). The relationships between surface wettability and chemical composition of our sample surfaces were established using XPS. The surface chemical compositions of each sample are summarized in Table 2. All

Three-gradient regular solution model for simple liquids wetting complex surface topologies

• Sabine Akerboom,
• Marleen Kamperman and
• Frans A. M. Leermakers

Beilstein J. Nanotechnol. 2016, 7, 1377–1396, doi:10.3762/bjnano.7.129

• curvature perpendicular to the plane in which the contact angle θ is observed, and the contact line does not move in a continuous way, but via depinning transitions. The pinning is not limited to kinks in the surface with angles θkink smaller than the angle θY. Even for θkink > θY, contact line pinning is

• scale, and does not entail details about the droplet shape close to the surface structures on a microscopic level. Another explanation of the difference in θ for a structured and unstructured surface of the same material is contact line pinning [17][18][19][20]. The three-phase contact line is hereby

• immobilized. Apart from chemical heterogeneities (which will not be discussed here), pinning occurs for a simple 1D system when the contact line encounters a kink in the surface, indicated with angle θkink in Figure 2. If θY < θkink, the angle of the droplet with respect to the surface should exceed θY in

High-resolution noncontact AFM and Kelvin probe force microscopy investigations of self-assembled photovoltaic donor–acceptor dyads

• Benjamin Grévin,
• Pierre-Olivier Schwartz,
• Laure Biniek,
• Martin Brinkmann,
• Nicolas Leclerc,
• Elena Zaborova and
• Stéphane Méry

Beilstein J. Nanotechnol. 2016, 7, 799–808, doi:10.3762/bjnano.7.71

• SPV is more negative. The black dotted squares indicate the location corresponding to the high-resolution images (shown later in Figure 9a,b). Schematic representation of an idealized D–A network and its band alignment with respect to the substrate. Here, we assume a Fermi level pinning of the donor

Assembling semiconducting molecules by covalent attachment to a lamellar crystalline polymer substrate

• Rainhard Machatschek,
• Patrick Ortmann,
• Renate Reiter,
• Stefan Mecking and
• Günter Reiter

Beilstein J. Nanotechnol. 2016, 7, 784–798, doi:10.3762/bjnano.7.70

• ]. Temperature, evaporation rate and polymer concentration affect nucleation probability and crystal growth rate. However, pinning of the contact line had the strongest influence on number density and size of the crystals. Therefore, on most samples, we observed arrays of many crystals which all had a length of

• vapor, the concentration was higher. The flux of solvent towards the contact line due to solvent evaporation led to transport of polymer molecules towards the contact line. A concentration gradient was built up, the magnitude of which depended on evaporation rate and the pinning behavior of the contact

• large enough, crystals could act as a pinning site for the polymer solution, thereby increasing the time available for the growth of crystals. The areal density and size of CPE45 crystals depended on the pinning behavior of the contact line. The crystal habit varied from leaf- or lentil-shaped to a

Magnetic switching of nanoscale antidot lattices

• Ulf Wiedwald,
• Joachim Gräfe,
• Kristof M. Lebecki,
• Maxim Skripnik,
• Felix Haering,
• Gisela Schütz,
• Paul Ziemann,
• Eberhard Goering and
• Ulrich Nowak

Beilstein J. Nanotechnol. 2016, 7, 733–750, doi:10.3762/bjnano.7.65

• artificial pinning sites for domain walls, blocking or even guiding their movement in specific directions during magnetic reversal [13][14]. Moreover, magnetic antidot lattices eventually lead to the formation of magnetic vortex structures [15]. In the extreme, the choice of large antidot diameters d > 0.75a

• smaller d/a ratio of about 0.5. FORC-MOKE investigations show magnetic switching dominated by domain wall pinning while the larger antidots reverse individually. Upon releasing the field from a fully magnetised state, we obtain stripe domains for large antidots of d = 165 nm at a = 200 nm by both

• domain wall pinning (by the antidots), as the reversal is not complete until a further increase of the counter field is applied. Further changes of the magnetisation can still be observed up to fields of 8000 Oe, while the reference film saturates at a field of 45 Oe (not shown). This can be regarded as

First-principles study of the structure of water layers on flat and stepped Pb electrodes

• Xiaohang Lin,
• Ferdinand Evers and
• Axel Groß

Beilstein J. Nanotechnol. 2016, 7, 533–543, doi:10.3762/bjnano.7.47

• . Still, the trajectories depicted in the lower panels of Figure 5c,e show that the water molecules move on Pb(311) and Pb(711) at a temperature of 140 K, but only in the direction parallel to the steps. So the pinning of the water molecules at the step edge prevents the water structure from being shifted

Chemiresistive/SERS dual sensor based on densely packed gold nanoparticles

• Sanda Boca,
• Cosmin Leordean,
• Simion Astilean and
• Cosmin Farcau

Beilstein J. Nanotechnol. 2015, 6, 2498–2503, doi:10.3762/bjnano.6.259

• perpendicular to the meniscus, and parallel to the translation direction. This ensures that during the 'go' phase no undesired/uncontrolled pinning by the electrodes occurs. Sensor characterization An optical image of the commercial IDE chip is presented in Figure 2a. As better seen in Figure 2b it consists of

Large area scanning probe microscope in ultra-high vacuum demonstrated for electrostatic force measurements on high-voltage devices

• Urs Gysin,
• Thilo Glatzel,
• Thomas Schmölzer,
• Adolf Schöner,
• Sergey Reshanov,
• Holger Bartolf and
• Ernst Meyer

Beilstein J. Nanotechnol. 2015, 6, 2485–2497, doi:10.3762/bjnano.6.258

• pinning at the surface at an energy around mid band gap (Ei = 4.6 eV). For SiC it was already observed before, that the measured work function seems to be largely independent of the doping concentration indicating a well defined Fermi-level pinning at approx. 4.6 eV due to intrinsic surface-state bands

• model indicating that the energy levels of the SiC surface consist of a filled band and an empty band, separated by a Hubbard gap of 1.6 eV. A pinning of the Fermi level was also observed by STM studies differing only by about 200 mV between p- and n-type doped SiC [54]. SiC was found to be in the

• transition between strong and no Fermi-level pinning which could also be tuned by passivation of the surface states with, e.g., hydrogen [55]. Furthermore, a large density of electrically active defects just below the conduction band of the polytype 4H-SiC has been reported to appear at interfaces and maybe

Tunable magnetism on the lateral mesoscale by post-processing of Co/Pt heterostructures

• Oleksandr V. Dobrovolskiy,
• Maksym Kompaniiets,
• Roland Sachser,
• Fabrizio Porrati,
• Christian Gspan,
• Harald Plank and
• Michael Huth

Beilstein J. Nanotechnol. 2015, 6, 1082–1090, doi:10.3762/bjnano.6.109

• [3] and memory [4], fabrication of Hall sensors [5] and cantilever tips [6] for magnetic force microscopy (MFM). In particular, the ability to tune the magnetization is the basic property needed for the realization of stacked nanomagnets [7], pinning of magnetic domain walls [8] and Abrikosov

Production, detection, storage and release of spin currents

• Michele Cini

Beilstein J. Nanotechnol. 2015, 6, 736–743, doi:10.3762/bjnano.6.75

• research of time-reversal violating new physics. Detailed calculations of such fields are under way. The present model neglects electron–electron interactions, but it is physically reasonable that adding to the Hamiltonian a correlation term such as would tend to reinforce the charge pinning effects

Manipulation of magnetic vortex parameters in disk-on-disk nanostructures with various geometry

• Maxim E. Stebliy,
• Alexander G. Kolesnikov,
• Alexey V. Ognev,
• Alexander S. Samardak and
• Ludmila A. Chebotkevich

Beilstein J. Nanotechnol. 2015, 6, 697–703, doi:10.3762/bjnano.6.70

• change of the magnetization velocity is zero matching the pinning of the vortex core by the small disk (marked by the circle). The shifted trajectory of the vortex core is shown in the inset in Figure 4c. There is no step on the return curve (when the field changing from −Hs to +Hs) due to a vortex core

• pinning, because the core is moving away from the small disk (see the inset in Figure 4d). The velocity of the vortex in the fields ranging from 20 to 350 Oe is almost constant (Figure 4d). The preservation of the loop asymmetry during multiple magnetization reversals shows that if the field is changed

A scanning probe microscope for magnetoresistive cantilevers utilizing a nested scanner design for large-area scans

• Tobias Meier,
• Alexander Förste,
• Ali Tavassolizadeh,
• Karsten Rott,
• Dirk Meyners,
• Roland Gröger,
• Günter Reiss,
• Eckhard Quandt,
• Thomas Schimmel and
• Hendrik Hölscher

Beilstein J. Nanotechnol. 2015, 6, 451–461, doi:10.3762/bjnano.6.46

• magnetization of the other electrode should remain in its initial orientation. Therefore, the MTJ has to be integrated into a TMR stack, which includes contact electrodes and a pinning mechanism to fix the magnetization of one reference electrode while the second sense electrode is free to rotate. To fix the

The capillary adhesion technique: a versatile method for determining the liquid adhesion force and sample stiffness

• Daniel Gandyra,
• Stefan Walheim,
• Stanislav Gorb,
• Wilhelm Barthlott and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2015, 6, 11–18, doi:10.3762/bjnano.6.2

• ], it is interesting to study the properties of the hairs of Salvinia molesta as a model for future developments. The key factors are the high water adhesion of the trichome tips (the “Salvinia effect”, [1]) and the high elasticity of the trichomes [2][3], which allows the pinning of the air–water

• on the surface of submerged Salvinia molesta leaves due to the pinning of the air–water interface [1]. The elasticity of the trichomes was also studied, as there are indications that it may also play a key role in the air layer persistence. This elasticity may allow a moving air–water interface to be