Adsorption of iron tetraphenylporphyrin on (111) surfaces of coinage metals: a density functional theory study

• Hao Tang,
• Nathalie Tarrat,
• Véronique Langlais and
• Yongfeng Wang

Beilstein J. Nanotechnol. 2017, 8, 2484–2491, doi:10.3762/bjnano.8.248

• The adsorption of the iron tetraphenylporphyrin (FeTPP) molecule in its deckchair conformation was investigated on Au(111), Ag(111) and Cu(111) surfaces by performing spin-polarized density functional theory (DFT) calculations taking into account both van der Waals (vdW) interaction and on-site

• shifts explain the direction of the charge transfer. In summary, by performing spin-polarized DFT and NEB calculations, we have identified two stable magnetic states of the free FeTPP molecule in its deckchair conformation (C2h). The two states (HS and IS) were separated by an activation barrier of 0.07

• strong enough to modify the ligand-field environment of Fe. This result reveals that an external permanent element such as a STM tip or an additional molecule is needed to use FeTPP or similar molecules as model system for molecular spin switches. Method and Computational Details Spin-polarized DFT

The interplay between spin densities and magnetic superexchange interactions: case studies of mono- and trinuclear bis(oxamato)-type complexes

• Azar Aliabadi,
• Bernd Büchner,
• Vladislav Kataev and
• Tobias Rüffer

Beilstein J. Nanotechnol. 2017, 8, 2245–2256, doi:10.3762/bjnano.8.224

• ] diamagnetic molecules [23] and even individual single-molecule magnets (SMMs) [24] were already successfully integrated, and spin-organic field-effect transistors [25] or spin-organic light-emitting diodes [26] were developed. Although it remains puzzling to understand the spin-polarized transport phenomena

Electronic structure, transport, and collective effects in molecular layered systems

• Torsten Hahn,
• Tim Ludwig,
• Carsten Timm and
• Jens Kortus

Beilstein J. Nanotechnol. 2017, 8, 2094–2105, doi:10.3762/bjnano.8.209

• ferromagnetic Fe thin film exhibits pronounced spin dependence. These investigations suggest the possibility of versatile applications in spintronic devices. The calculations on model systems with gold contacts show that it is possible to obtain spin-polarized currents from both phthalocyanine-based devices

• function of the bias voltage is obtained from the spin-polarized current within the DFT-NEGF method. Absolute value squared of the tunneling amplitude a) between the STM tip and a CoPc HOMO on a graphene substrate and b) between the tip and a representative low-energy Bloch-type substrate state, as

Spin-dependent transport and functional design in organic ferromagnetic devices

• Guichao Hu,
• Shijie Xie,
• Chuankui Wang and
• Carsten Timm

Beilstein J. Nanotechnol. 2017, 8, 1919–1931, doi:10.3762/bjnano.8.192

• hyperfine interactions in organic materials are usually weak [4], which induces a long spin relaxation time and makes organic materials ideal for spin-polarized transport applications. Organic molecules may form a soft interface with metals and ferromagnets via chemical adsorption. The interfacial orbital

• for the electrodes vary according to the material adopted. For details on the parameters, see the related works [31][32][33]. Spin filtering in metal/OF/metal devices A spin filter is meant to generate a strongly spin-polarized current from an unpolarized current source and is a crucial element for

• bias of 0.8 V, only the spin-up LUMO falls into the bias window and contributes to the current. Therefore, the current is nearly fully spin polarized. When the bias increases, additional spin-up and spin-down orbitals will enter the bias window alternately, which results in the oscillation of the SP

Adsorption and diffusion characteristics of lithium on hydrogenated α- and β-silicene

• Fadil Iyikanat,
• Ali Kandemir,
• Cihan Bacaksiz and
• Hasan Sahin

Beilstein J. Nanotechnol. 2017, 8, 1742–1748, doi:10.3762/bjnano.8.175

• less than 10−4 eV/Å. To hinder interactions between the adjacent cells, at least 12 Å vacuum space was used along the z-direction. All calculations were performed taking into account the spin-polarized case. Analysis of the charge transfers in the structures was determined by the Bader technique [51

Spin-chemistry concepts for spintronics scientists

• Konstantin L. Ivanov,
• Alexander Wagenpfahl,
• Carsten Deibel and
• Jörg Matysik

Beilstein J. Nanotechnol. 2017, 8, 1427–1445, doi:10.3762/bjnano.8.143

• thin organic semiconductor layer is sandwiched between two ferromagnetic electrodes [24]. A spin-polarized current is injected from one of these electrodes and transported through the semiconductor. Another type also implements spin current, but without charge current, in the structure ferromagnetic

The role of 2D/3D spin-polarization interactions in hybrid copper hydroxide acetate: new insights from first-principles molecular dynamics

• Ziyad Chaker,
• Guido Ori,
• Mauro Boero and
• Carlo Massobrio

Beilstein J. Nanotechnol. 2017, 8, 857–860, doi:10.3762/bjnano.8.86

• ., 0%) and the maximally spin polarized layer case (i.e., 100% F-in). Typical examples of the obtained spin distributions are shown in Figure 3 for S = 0 and S = 8 at 0 GPa and 7.5 GPa. By looking at the partial populations with different F-in deviation, the following tendencies can be observed. For S

• = 0, the pressure induces a decrease of the spin distributions with Σ = 0 whereas the content of spin distributions with a large 2D spin polarization (F-in > 25%) increases significantly. Conversely, for S = 8, an opposite trend can be noticed, with a decrease of the 2D spin polarized distributions (F

Electron energy relaxation under terahertz excitation in (Cd_1−xZn_x)₃As₂ Dirac semimetals

• Alexandra V. Galeeva,
• Ivan V. Krylov,
• Konstantin A. Drozdov,
• Anatoly F. Knjazev,
• Alexey V. Kochura,
• Alexander P. Kuzmenko,
• Vasily S. Zakhvalinskii,
• Sergey N. Danilov,
• Ludmila I. Ryabova and
• Dmitry R. Khokhlov

Beilstein J. Nanotechnol. 2017, 8, 167–171, doi:10.3762/bjnano.8.17

• insulators form a class of materials possessing a different electron energy spectrum at the surface as compared to the bulk. The bulk energy spectrum of a topological insulator is typically observed for a semiconductor, whereas spin-polarized gapless electron states with a Dirac linear dispersion relation

• the electron mobility observed in Cd3As2, which is up to 107 cm2/(V·s) [9][11]. The question concerning formation of spin-polarized surface electron states in 3D Dirac semimetals remains open. According to [9][11], the surface states of Cd3As2 do not possess any spin texture. However, the authors do

• not exclude the possibility that the spin-polarized surface states may be formed, but the sensitivity of the method used does not allow discriminating these states. In this paper, we show that there is an indirect confirmation for the formation of spin-polarized electron states with high mobility on

Ferromagnetic behaviour of ZnO: the role of grain boundaries

• Boris B. Straumal,
• Svetlana G. Protasova,
• Andrei A. Mazilkin,
• Eberhard Goering,
• Gisela Schütz,
• Petr B. Straumal and
• Brigitte Baretzky

Beilstein J. Nanotechnol. 2016, 7, 1936–1947, doi:10.3762/bjnano.7.185

• direct evidence can be obtained from the local-probe method of low-energy muon spin relaxation (LE-µSR) [13]. This method is based on the idea to implant spin-polarized low-energy positive muons into ZnO. Due to their positive charge, the low-energy muons are trapped in the interstitial lattice sites

• measurements the positive muons were implanted into the films. The positive muons were 100% spin polarized. The spin polarization was parallel to the sample surface. The measurements were done in zero field at different temperatures of −223, −103, and 23 °C. Different sample implantation depths were also used

Nonlinear thermoelectric effects in high-field superconductor-ferromagnet tunnel junctions

• Stefan Kolenda,
• Peter Machon,
• Detlef Beckmann and
• Wolfgang Belzig

Beilstein J. Nanotechnol. 2016, 7, 1579–1585, doi:10.3762/bjnano.7.152

• ][6] and fully spin-polarized quasiparticle currents [7][8][9]. Superconductor/normal-metal hybrid structures can also be used for local electron thermometry and microrefrigeration [10][11]. Recently, large spin-dependent thermoelectric effects were predicted [12][13][14][15][16] and experimentally

Filled and empty states of Zn-TPP films deposited on Fe(001)-p(1×1)O

• Gianlorenzo Bussetti,
• Alberto Calloni,
• Rossella Yivlialin,
• Andrea Picone,
• Federico Bottegoni and
• Marco Finazzi

Beilstein J. Nanotechnol. 2016, 7, 1527–1531, doi:10.3762/bjnano.7.146

• are distinctive structures well known for their spin-polarized character [13]. The small feature at about 4.0 eV is usually attributed to an image state resonance that demonstrates the very good quality of the surface preparation [14]. The 20 ML thick sample shows the main features of the Zn-TPP

Electron and heat transport in porphyrin-based single-molecule transistors with electro-burnt graphene electrodes

• Hatef Sadeghi,
• Sara Sangtarash and
• Colin J. Lambert

Beilstein J. Nanotechnol. 2015, 6, 1413–1420, doi:10.3762/bjnano.6.146

• the ground state energy (see Computational Methods). We carried out a spin-polarized calculation since the d orbitals of the Zn atom could be filled to different degrees. It is well-known that Kohn–Sham DFT eigenvalues usually underestimate the HOMO–LUMO gap and DFT typically does not predict their

Interaction of electromagnetic radiation in the 20–200 GHz frequency range with arrays of carbon nanotubes with ferromagnetic nanoparticles

• Agylych Atdayev,
• Alexander L. Danilyuk and
• Serghej L. Prischepa

Beilstein J. Nanotechnol. 2015, 6, 1056–1064, doi:10.3762/bjnano.6.106

• material are currently the subject of intensive study. The properties of such materials can be tuned by the external magnetic field, spin-polarized current or electromagnetic radiation. In conventional ferromagnetic materials, the magnetic properties are determined by the domain structure and domain walls

Production, detection, storage and release of spin currents

• Michele Cini

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

• spin-polarized currents into the wires by using rotating magnetic fields or letting the ring rotate around the wire. This method works without any need for a spin–orbit interaction, and without stringent requirements about the conduction band filling. Besides, they can be used to pump spin, rather than

• . Conclusion I presented a theoretical study of tight-binding model devices consisting of a ring laterally connected to a wire and designed to produce spin polarized currents at half filling. A tangent time-dependent magnetic field in the plane of the ring can be used to pump a magnetic, i.e., purely spin

Chains of carbon atoms: A vision or a new nanomaterial?

• Florian Banhart

Beilstein J. Nanotechnol. 2015, 6, 559–569, doi:10.3762/bjnano.6.58

• polarization whether they are metallic or semiconducting (depending on the edge of the graphene ribbon at the contact). Hence, carbon chains connected to graphene ribbons could be used as spin polarized semiconductors. While Zanolli et al. did not obtain a magnetic moment on even-number chains, a triplet state

Advances in NO₂ sensing with individual single-walled carbon nanotube transistors

• Kiran Chikkadi,
• Matthias Muoth,
• Cosmin Roman,
• Miroslav Haluska and
• Christofer Hierold

Beilstein J. Nanotechnol. 2014, 5, 2179–2191, doi:10.3762/bjnano.5.227

• ][39][40][41][42][43]. Although the first calculations [39][40] suggested a charge transfer upon physisorption, Santucci et al. [43] showed that this charge transfer disappeared when spin-polarized treatment was used in the calculations. Yim et al. [44] have suggested that a pairwise chemisorption of

Numerical investigation of the effect of substrate surface roughness on the performance of zigzag graphene nanoribbon field effect transistors symmetrically doped with BN

• Majid Sanaeepur,
• Arash Yazdanpanah Goharrizi and
• Mohammad Javad Sharifi

Beilstein J. Nanotechnol. 2014, 5, 1569–1574, doi:10.3762/bjnano.5.168

• to the width of the GNR [7][8][9][10][11]. Armchair graphene nanoribbons (AGNRs) are non-magnetic. Zigzag graphene nanoribbons (ZGNRs), however, have a spin-polarized ground state and a high density of states localized at the zigzag edges of the ribbon [8][12][13][14]. Nonetheless, the energy of the

• spin-polarized state is only 20 meV per edge atom lower than that of the non-polarized state [15][16]. In addition, the spin-polarized state becomes unstable with respect to the non-polarized state in the presence of a ballistic current through the GNR [17]. Moreover, the magnetization is theoretically

Sublattice asymmetry of impurity doping in graphene: A review

• James A. Lawlor and
• Mauro S. Ferreira

Beilstein J. Nanotechnol. 2014, 5, 1210–1217, doi:10.3762/bjnano.5.133

• ][50] and produce spin-polarized current [51][52]. Much work has been done studying how the placement of dopants affects the properties of nanoribbons. DFT approaches, using a periodic system of dopants [53][54], and a more general Kubo–Greenwood approach [37] have shown that electron transport is

• bombardement [63], which could be combined with the high temperature annealing process discussed previously. The experimental realisation of spin-polarized transport should also be pursued, and could spark additional interest in this research area beyond quasi-ballistic transport. Investigation of the effects

Designing magnetic superlattices that are composed of single domain nanomagnets

• Derek M. Forrester,
• Feodor V. Kusmartsev and
• Endre Kovács

Beilstein J. Nanotechnol. 2014, 5, 956–963, doi:10.3762/bjnano.5.109

• detection devices for spintronics [27][28][29][30]. The ferromagnetic materials are ideal contacts for creating these spintronic devices on, for example, a single layer of graphene [29]. A magnetic ratchet device could be used to inject, at room temperature, a reservoir of spin-polarized electrons for

Volcano plots in hydrogen electrocatalysis – uses and abuses

• Paola Quaino,
• Fernanda Juarez,
• Elizabeth Santos and
• Wolfgang Schmickler

Beilstein J. Nanotechnol. 2014, 5, 846–854, doi:10.3762/bjnano.5.96

• . Nickel and cobalt are the only metals that lie on the descending branch, and they are worth a special look. Nickel Nickel and cobalt are very similar, and we focus on Ni(111), which is the densest and most stable surface. Nickel is one of the few metals that are spin polarized, and the d bands for spin

Confinement dependence of electro-catalysts for hydrogen evolution from water splitting

• Mikaela Lindgren and
• Itai Panas

Beilstein J. Nanotechnol. 2014, 5, 195–201, doi:10.3762/bjnano.5.21

• -function on each hydrogen atom. Systematic spin polarized calculations were performed. A 4 × 4 × 1 k-point set for sampling the Brillouin zone was compared to a 2 × 2 × 1 k-point set, and the latter was found to suffice. In order to reduce the computational effort, inert electron shells were described

Charge and spin transport in mesoscopic superconductors

• M. J. Wolf,
• F. Hübler,
• S. Kolenda and
• D. Beckmann

Beilstein J. Nanotechnol. 2014, 5, 180–185, doi:10.3762/bjnano.5.18

• models. Conclusion: The observed long-range chargeless spin transport opens a new path to manipulate and utilize the quasiparticle spin in superconductor nanostructures. Keywords: spintronics; superconductor–ferromagnet hybrids; Introduction The investigation of spin-polarized transport in hybrid

• observed subsequently, spin-polarized transport did not attract much attention until the discovery of the giant magnetoresistance (GMR) [5][6][7] and its technical applications. In superconductors, electrons are bound in Cooper pairs, which usually have a singlet structure and therefore carry only charge

• polarity. These features can be attributed to spin injection into the Zeeman-split density of states of the superconductor [17][18][22][26], which is probed by the ferromagnetic detector in this configuration. Spin-polarized tunneling can be described by two independent conductances g↓ and g↑ for the two

Core level binding energies of functionalized and defective graphene

• Toma Susi,
• Markus Kaukonen,
• Paula Havu,
• Mathias P. Ljungberg,
• Paola Ayala and
• Esko I. Kauppinen

Beilstein J. Nanotechnol. 2014, 5, 121–132, doi:10.3762/bjnano.5.12

• elements such as carbon and oxygen with only one core state, but requiring a spin-polarized calculation for the system of interest. A similar methodology, however employing pseudo-potentials [17], was previously used to study oxidized graphene. The energy of the core level excitation was determined in the

Nanoglasses: a new kind of noncrystalline materials

• Herbert Gleiter

Beilstein J. Nanotechnol. 2013, 4, 517–533, doi:10.3762/bjnano.4.61

• coupling in the nanoglass interfaces. The same conclusion is suggested by the magnetic Compton profile of the chemically identical nanoglass [21] indicating that the itinerant ferromagnetism of the Fe90Sc10 nanoglass is based on spin-polarized sp-like itinerant electrons [21][22][23][24]. If the Young’s

• in the nanoglass is caused by negative spin polarized sp-like itinerant electrons [21][22][23][24]. Molecular dynamics simulation of the consolidation of a nanoglass at 300 K [27]. The nanoglass is obtained by sintering nanometer-sized (5 nm diameter) glassy spheres (of Ge) at a pressure of 5 GPa. (e

Sub-10 nm colloidal lithography for circuit-integrated spin-photo-electronic devices

• Adrian Iovan,
• Marco Fischer,
• Roberto Lo Conte and
• Vladislav Korenivski

Beilstein J. Nanotechnol. 2012, 3, 884–892, doi:10.3762/bjnano.3.98

• and, if needed, tuning the array lattice spacing to achieve better interference of spin-wave modes. Another interesting application of the spin-majority/minority Fe/Fe0.7Cr0.3 contact-core material used above is the spin-flip photon-emission effect [15][24][25], which requires spin-polarized and

• exchange splitting in the ferromagnetic point contact core (10–100 mV, see [24][25] for more details). Such high-bias, high-density, spin-polarized injection produces large nonequilibrium spin accumulation in the contact core, which allows spin-flip photon-emission transitions, vertical in the momentum of