Charged particle single nanometre manufacturing

• Philip D. Prewett,
• Cornelis W. Hagen,
• Claudia Lenk,
• Steve Lenk,
• Marcus Kaestner,
• Tzvetan Ivanov,
• Ahmad Ahmad,
• Ivo W. Rangelow,
• Xiaoqing Shi,
• Stuart A. Boden,
• Alex P. G. Robinson,
• Dongxu Yang,
• Sangeetha Hari,
• Marijke Scotuzzi and
• Ejaz Huq

Beilstein J. Nanotechnol. 2018, 9, 2855–2882, doi:10.3762/bjnano.9.266

• mostly determined by the directionality of the etching, which is preferably anisotropic, and the surface quality after etching. The height ratio, defined as the ratio between the height of the mask before etching and the height of the structure after etching, allows an estimate of the relative etching

Controlling surface morphology and sensitivity of granular and porous silver films for surface-enhanced Raman scattering, SERS

• Sherif Okeil and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2018, 9, 2813–2831, doi:10.3762/bjnano.9.263

• surface. However, the formation of a particulate morphology and the faceting of the silver surface is best explained by an anisotropic etching or a restructuring process of the silver surface by reactive nitrogen plasma species such as N2+, N2* (excited nitrogen), N•+ and N• (nitrogen radicals) [79]. The

Biomimetic surface structures in steel fabricated with femtosecond laser pulses: influence of laser rescanning on morphology and wettability

• Camilo Florian Baron,
• Alexandros Mimidis,
• Daniel Puerto,
• Evangelos Skoulas,
• Emmanuel Stratakis,
• Javier Solis and
• Jan Siegel

Beilstein J. Nanotechnol. 2018, 9, 2802–2812, doi:10.3762/bjnano.9.262

• for mimicking this structure by exploiting self-organization mechanisms. In particular, employing a combination of such isotropic microstructures shown in Figure 2B (which determine the water contact angle, as will be shown in Figure 4) with an anisotropic overstructure with dimensions of hundreds of

Magnetic and luminescent coordination networks based on imidazolium salts and lanthanides for sensitive ratiometric thermometry

• Pierre Farger,
• Cédric Leuvrey,
• Mathieu Gallart,
• Pierre Gilliot,
• Guillaume Rogez,
• João Rocha,
• Duarte Ananias,
• Pierre Rabu and
• Emilie Delahaye

Beilstein J. Nanotechnol. 2018, 9, 2775–2787, doi:10.3762/bjnano.9.259

• factors. The structures were solved by direct methods using SIR92 [73], and refined against F2 by full-matrix least-squares methods using SHELXL-2014 with anisotropic displacement parameters for all non-hydrogen atoms [74][75]. All calculations were performed by using the crystal structure

Low cost tips for tip-enhanced Raman spectroscopy fabricated by two-step electrochemical etching of 125 µm diameter gold wires

• Antonino Foti,
• Francesco Barreca,
• Enza Fazio,
• Cristiano D’Andrea,
• Paolo Matteini,
• Onofrio Maria Maragò and
• Pietro Giuseppe Gucciardi

Beilstein J. Nanotechnol. 2018, 9, 2718–2729, doi:10.3762/bjnano.9.254

• wire diameter at the meniscus is thinner than the portion immersed in the liquid. This difference is likely due to the anisotropic distribution of the reaction products (AuCl4− and AuCl2−) along the wire surface that hinders the renewal of fresh etchant. The reaction products generated at the meniscus

• fall due to gravity, covering the surface of the wire still immersed in the bulk solution, affecting the concentration distribution of the chlorine ions along the wire. A higher local concentration of Cl− ions at the meniscus with respect to the bulk can justify the observed anisotropic etching rate

Evidence of friction reduction in laterally graded materials

• Roberto Guarino,
• Gianluca Costagliola,
• Federico Bosia and
• Nicola Maria Pugno

Beilstein J. Nanotechnol. 2018, 9, 2443–2456, doi:10.3762/bjnano.9.229

• vertical stress distribution, FEM simulations display an anisotropic behaviour when considering a positive or a negative gradient. This is equivalent to considering the same sign of the gradient but with an opposite sliding direction. This result can be attributed to the vertical stress distribution at the

• friction force from the region with higher thresholds is more influential, so that the maximum of the friction force occurs later during the detachment process and not shortly after its beginning. Thus, while SBM cannot capture anisotropic behaviour emerging from 3D deformation effects occurring in the

• within 1% as shown in Figure 7. Again, the FEM results are anisotropic with respect to Δ, for the reasons explained above. However, the effect of the gradient on the dynamic friction cannot be fully captured by a formulation only based on an Amontons–Coulomb friction law, as in the case of the SBM

Magnetism and magnetoresistance of single Ni–Cu alloy nanowires

• Andreea Costas,
• Camelia Florica,
• Elena Matei,
• Maria Eugenia Toimil-Molares,
• Ionel Stavarache,
• Andrei Kuncser,
• Victor Kuncser and
• Ionut Enculescu

Beilstein J. Nanotechnol. 2018, 9, 2345–2355, doi:10.3762/bjnano.9.219

• magnetic elements, usually of dipolar type. In this paper we report on a strategy of studying the magnetic properties of single Ni–Cu alloy nanowires of high aspect ratio via specific anisotropic magnetoresistance measurements. In this respect, arrays of nanowires have been fabricated by means of templated

• , one observes the lack of any magnetoresistive effect in the parallel geometry and a magnetoresistive effect of the order of percent in the perpendicular geometry. Such behavior clearly reminds on anisotropic magnetoresistance effects the physical mechanisms of which were excellently described already

• segments still exhibit the high aspect ratio required for shape anisotropy and hence, their lengths of hundreds of nanometers are consistent with anisotropic magnetoresistive effects and not with a GMR spin-valve configuration of a segmented structure with magnetic/nonmagnetic layers of nanometer thickness

Performance analysis of rigorous coupled-wave analysis and its integration in a coupled modeling approach for optical simulation of complete heterojunction silicon solar cells

• Ziga Lokar,
• Benjamin Lipovsek,
• Marko Topic and
• Janez Krc

Beilstein J. Nanotechnol. 2018, 9, 2315–2329, doi:10.3762/bjnano.9.216

• anisotropic etching), while the thickness of ITO and a-Si:H was kept constant. In Figure 7 the effects of PF variation on reflectance and on the corresponding JSC gain are shown. The front part of the solar cell was simulated by RCWA as in previous sections. In these simulations, ten modes and 300 sublayers

Surface energy of nanoparticles – influence of particle size and structure

• Dieter Vollath,
• Franz Dieter Fischer and
• David Holec

Beilstein J. Nanotechnol. 2018, 9, 2265–2276, doi:10.3762/bjnano.9.211

• considered. In this case, the number of next neighbors is proportional the volume of the intersection between the particle and a sphere with the diameter 2r having its center at the surface of the particle. (Certainly, this simplified treatment is not expedient for anisotropic materials.) These

Influence of the thickness of an antiferromagnetic IrMn layer on the static and dynamic magnetization of weakly coupled CoFeB/IrMn/CoFeB trilayers

• Deepika Jhajhria,
• Dinesh K. Pandya and
• Sujeet Chaudhary

Beilstein J. Nanotechnol. 2018, 9, 2198–2208, doi:10.3762/bjnano.9.206

• , AF-based spintronics is gaining momentum because of the unique properties such as zero net magnetization, no stray fields, low magnetic susceptibility, large spin–orbit coupling, ultrafast dynamics and large magneto-transport effects [2][3][4][5][6]. Several of the effects such as tunnel anisotropic

• function of the angle θ. The two-fold symmetry for all samples clearly indicates the existence of the uniaxial magnetic anisotropy (UMA). This UMA results from the breakdown of the azimuthal symmetry in the deposited films, which is likely to be caused by the anisotropic stress in the films generated due

• to the oblique deposition geometry [39]. Since CoFeB is highly sensitive to this induced anisotropic stress (owing to their large positive saturation magnetostriction coefficient λs [40]), the deposition geometry effectively results in the observed UMA [41]. The UMA in films is found to be directly

Electrospun one-dimensional nanostructures: a new horizon for gas sensing materials

• Muhammad Imran,
• Nunzio Motta and
• Mahnaz Shafiei

Beilstein J. Nanotechnol. 2018, 9, 2128–2170, doi:10.3762/bjnano.9.202

• improves the performance of electrospun fibers/mats. In addition, the electrospun fibers/mats may reduce corrosion and/or oxidation in NPs, especially those with anisotropic structure [40]. Depending on the type of polymer and NPs, electrospun fibers incorporated with NPs are optimized for specific

• applications. This approach shows good potential for applications involving the self-assembly of anisotropic NPs to generate new functional devices [63]. There are two major methods for producing electrospun NP fibers [40]: (i) “indirect synthesis”, that requires some post-processing methods after

Spin-coated planar Sb₂S₃ hybrid solar cells approaching 5% efficiency

• Pascal Kaienburg,
• Benjamin Klingebiel and
• Thomas Kirchartz

Beilstein J. Nanotechnol. 2018, 9, 2114–2124, doi:10.3762/bjnano.9.200

• [32] or liquid [6] sulfur sources might reduce the density of electronic defects in Sb2S3 for certain deposition methods that leave sulfur deficient films [29][72]. Another aim in terms of fabrication is to exploit the anisotropic nature of Sb2S3 by aligning the 1D ribbons with the direction of charge

High-throughput synthesis of modified Fresnel zone plate arrays via ion beam lithography

• Kahraman Keskinbora,
• Umut Tunca Sanli,
• Margarita Baluktsian,
• Corinne Grévent,
• Markus Weigand and
• Gisela Schütz

Beilstein J. Nanotechnol. 2018, 9, 2049–2056, doi:10.3762/bjnano.9.194

• . Figure 2b and Figure 2c show some hard Au grains remained relatively unharmed by the ion beam due to the strong dependence of the ion beam damage on the crystal orientation concerning anisotropic sputter yield and channeling effects [42]. These grains have a random spatial distribution, which renders

Recent highlights in nanoscale and mesoscale friction

• Andrea Vanossi,
• Dirk Dietzel,
• Andre Schirmeisen,
• Ernst Meyer,
• Rémy Pawlak,
• Thilo Glatzel,
• Marcin Kisiel,
• Shigeki Kawai and
• Nicola Manini

Beilstein J. Nanotechnol. 2018, 9, 1995–2014, doi:10.3762/bjnano.9.190

Correlative electrochemical strain and scanning electron microscopy for local characterization of the solid state electrolyte Li_1.3Al_0.3Ti_1.7(PO₄)₃

• Nino Schön,
• Deniz Cihan Gunduz,
• Shicheng Yu,
• Hermann Tempel,
• Roland Schierholz and
• Florian Hausen

Beilstein J. Nanotechnol. 2018, 9, 1564–1572, doi:10.3762/bjnano.9.148

• observed ESM amplitude signal. Electrostatic interactions are discussed to be an important additional parameter that can influence ESM experiments [28][30][31] and will be the subject of future research. Additionally, LATP is known to have a strong anisotropic thermal expansion [3]. LTP, which has the same

• structure, exhibits an anisotropic reaction upon lithium intercalation; the a-axis contracts while the c-axis expands with the transformation from LiTi2(PO4)3 to Li3Ti2(PO4)3 [32]. Hence, LATP might show similar behavior upon (de)-lithiation and its electrostatic interaction can be expected to be strongly

• anisotropic. A simple interpretation of the ESM amplitude signal solely based on Vegard’s Law is therefore demanding and would require a correlative EBSD analysis of the area to retrieve the actual crystallographic orientation [21]. However, a thorough analysis is out of the scope of the current study but is

Robust midgap states in band-inverted junctions under electric and magnetic fields

• Álvaro Díaz-Fernández,
• Natalia del Valle and
• Francisco Domínguez-Adame

Beilstein J. Nanotechnol. 2018, 9, 1405–1413, doi:10.3762/bjnano.9.133

• , v is an interband matrix element having dimensions of velocity and it is assumed scalar, corresponding to isotropic bands around the L point. It is worth mentioning that the bands of IV–VI compounds around the L points are actually anisotropic. Nevertheless, this anisotropy can be absorbed in the

• Figure 2. Hence, the Fermi velocity becomes anisotropic and can actually be modulated with the magnetic field. It is expected that the application of an electric field will lead to further reduction of the Fermi velocity [25]. We will prove later that this is actually the case. In Figure 3a we show a

• magnetic field parallel to the band-inverted junction is applied. The original Dirac cone widens only in the direction perpendicular to the magnetic field but remarkably the dispersion relation remains gapless. Hence, the Fermi velocity becomes anisotropic and the combination of both electric and magnetic

Predicting the strain-mediated topological phase transition in 3D cubic ThTaN₃

• Chunmei Zhang and
• Aijun Du

Beilstein J. Nanotechnol. 2018, 9, 1399–1404, doi:10.3762/bjnano.9.132

• effective mass (m*) of ThTaN3 at the conduction band minimum (CBM) is estimated from the curvature of the electronic band dispersion, that is, the formula where E and k are the band energy and reciprocal lattice vector. For anisotropic materials, where i, j and k label the transport direction along the x

Induced smectic phase in binary mixtures of twist-bend nematogens

• Anamarija Knežević,
• Irena Dokli,
• Marin Sapunar,
• Suzana Šegota,
• Ute Baumeister and
• Andreja Lesac

Beilstein J. Nanotechnol. 2018, 9, 1297–1307, doi:10.3762/bjnano.9.122

• the anisotropic intermolecular energy parameter between the unlike species is the geometric mean of the anisotropic interaction parameters between the like species. The linearity of both transition temperatures was also observed in the mixtures of methylene and ether-linked dimers and used for

Formation and development of nanometer-sized cybotactic clusters in bent-core nematic liquid crystalline compounds

• Yuri P. Panarin,
• Sithara P. Sreenilayam,
• Jagdish K. Vij,
• Anne Lehmann and
• Carsten Tschierske

Beilstein J. Nanotechnol. 2018, 9, 1288–1296, doi:10.3762/bjnano.9.121

• -Carlo simulation for biaxial particles via an anisotropic pair potential [3]. Such a system exhibits three phases: biaxial crystalline at absolute zero temperature, uniaxial nematic and a rotationally disordered isotropic phase. In spite of the several theoretical studies having been successfully

• correlations among the neighboring molecules were revealed and the cybotactic clusters were established [35][36][48]. This was the first successful attempt for determining the cluster size by using the Maier–Meier equations using dielectric parameters such as anisotropic permittivity and the anisotropic

Optical orientation of nematic liquid crystal droplets via photoisomerization of an azodendrimer dopant

• Sergey A. Shvetsov,
• Alexander V. Emelyanenko,
• Natalia I. Boiko,
• Alexander S. Zolot'ko,
• Yan-Song Zhang,
• Jui-Hsiang Liu and
• Alexei R. Khokhlov

Beilstein J. Nanotechnol. 2018, 9, 870–879, doi:10.3762/bjnano.9.81

• returns into trans form. The anisotropic interaction of azobenzene molecules with each other, as well as with their environment, essentially depends on their shape (rod-like for trans isomers and having no distinct anisometry for cis isomers). This leads to the modification of physical properties of

• trans and cis isomers are determined by the quantum yields (Φtrans and Φcis) and absorption coefficients and do not depend on exposure time and light intensity. In the case of an anisotropic solution, the light absorption depends on the direction of light propagation. In contrast to disordered cis

Facile phase transfer of gold nanorods and nanospheres stabilized with block copolymers

• Yaroslav I. Derikov,
• Georgiy A. Shandryuk,
• Raisa V. Talroze,
• Alexander A. Ezhov and
• Yaroslav V. Kudryavtsev

Beilstein J. Nanotechnol. 2018, 9, 616–627, doi:10.3762/bjnano.9.58

• anisotropic. Their possible coupling with nanorods, as the simplest anisometric nanoparticles, is of emerging interest in recent experimental [6][7][8] and theoretical [9][10][11][12] research. In the case of Au nanoparticles, which are the focus of the current study, a number of synthetic routes are

Dynamic behavior of nematic liquid crystal mixtures with quantum dots in electric fields

• Emil Petrescu,
• Cristina Cirtoaje and
• Octavian Danila

Beilstein J. Nanotechnol. 2018, 9, 399–406, doi:10.3762/bjnano.9.39

• ], the polarization field around a spherical cavity inside a dielectric medium is proportional to the applied field, so: Inside an anisotropic dielectric (the liquid crystal) the spherical cavity changes into an ellipsoid with the semi-axes and , where b is the cavity radius, is the parallel

Review: Electrostatically actuated nanobeam-based nanoelectromechanical switches – materials solutions and operational conditions

• Liga Jasulaneca,
• Jelena Kosmaca,
• Raimonds Meija,
• Jana Andzane and
• Donats Erts

Beilstein J. Nanotechnol. 2018, 9, 271–300, doi:10.3762/bjnano.9.29

• . Semiconductors Silicon and germanium: Both Si and Ge have a long history as semiconductor device materials. Comparable relatively high Young’s moduli (Si, 130–188 GPa [129] and Ge, 103–150 GPa) [130][131] make these materials useful for applications in NEM devices. Due to the possibility of anisotropic etching

Liquid-crystalline nanoarchitectures for tissue engineering

• Baeckkyoung Sung and
• Min-Ho Kim

Beilstein J. Nanotechnol. 2018, 9, 205–215, doi:10.3762/bjnano.9.22

• schematic of LC nanoarchitectures interacting with cells. The LC order of the biopolymers has three major implications for the biological systems: (1) cell–matrix interaction, (2) formation of ECM-based connective tissues, and (3) cellular and subcellular level physiology. First, the spatially anisotropic

• nanoscale topographies [93][94]. LC elastomer scaffolds in nematic and smectic-A phases Liquid crystal elastomers (LCEs) are crosslinked 3D networks of rubber-like synthetic polymers exhibiting orientational and/or positional order [95]. Due to the tunable malleability and highly anisotropic shape change in

• induced 2D and 3D aligned cell growth in response to the lamellar molecular structure of LCE matrices, with tunable porosity and crosslinking density [99][100][101]. In addition, the 3D anisotropic cell scaffolds can be fabricated by using nematic LCE microspheres as building blocks by tuning elastic

Design of photonic microcavities in hexagonal boron nitride

• Sejeong Kim,
• Milos Toth and
• Igor Aharonovich

Beilstein J. Nanotechnol. 2018, 9, 102–108, doi:10.3762/bjnano.9.12

• the emitters. Here, we design 2D and 1D PCCs using anisotropic indices of hBN. The influence of underlying substrates and material absorption are investigated, and spontaneous emission rate enhancements are calculated. Our results are promising for future quantum photonic experiments with hBN

• . Keywords: anisotropic optical materials; boron nitride; photonic crystals; Introduction Hexagonal boron nitride (hBN) has recently emerged as an interesting platform for nanophotonics. This is mainly due to its promising hyperbolic properties [1][2] as well as the ability to host a range of single photon