Out-of-plane surface patterning by subsurface processing of polymer substrates with focused ion beams

• Serguei Chiriaev,
• Luciana Tavares,
• Vadzim Adashkevich,
• Arkadiusz J. Goszczak and
• Horst-Günter Rubahn

Beilstein J. Nanotechnol. 2020, 11, 1693–1703, doi:10.3762/bjnano.11.151

• of the polymer. Effects of subsurface and surface processes on the surface morphology have been studied for three polymer materials: poly(methyl methacrylate), polycarbonate, and polydimethylsiloxane, by using focused ion beam irradiation with He+, Ne+, and Ga+. Thin films of a Pt60Pd40 alloy and of

• -plane features, at the nanoscale, of the pre-deposited films. Ion irradiation of the Au-coated samples results in delamination, bulging, and perforation of the Au film, which is attributed to the accumulation of gases from radiolysis at the film–substrate interface. The irradiation with Ne+ and Ga+ ions

• interest within diverse fields of materials science and technology [1]. In recent years, the capabilities of FIBs have been substantially enhanced leading to a broad range of applications by the implementation of light ion beams (He+ and Ne+) emitted by a gas field ion source (GFIS). This has enabled

Helium ion microscope – secondary ion mass spectrometry for geological materials

• Matthew R. Ball,
• Richard J. M. Taylor,
• Joshua F. Einsle,
• Fouzia Khanom,
• Christelle Guillermier and
• Richard J. Harrison

Beilstein J. Nanotechnol. 2020, 11, 1504–1515, doi:10.3762/bjnano.11.133

• ion stream of He+ or Ne+, with a very small probe size (0.5 nm for He+ and less than 3 nm for Ne+). Primary ion currents of 1–10 pA were applied to the samples with acceleration voltages between 10,000 and 20,000 keV. Positive secondary ions of Li+ were extracted by the application of a 500 V

• , which is typically measured after the analysis: The sputtering yield depends on the nature of the atoms as well as the matrix in which they are bound. This yield can be predicted semi-empirically for a primary Ne beam [17]. Figure 3 shows how the calculated yield of different atoms varies for a silicate

• . The calculated sputtering yield as a function of the atomic number for a 10 kV primary Ne beam impacting a silicate glass matrix for a low-density glass (2.2 g·cm−3, blue) and a high-density glass (3.3 g·cm−3, red), calculation after [17]. Reflected-light micrograph of the analysed Spodumene grain

Transient coating of γ-Fe₂O₃ nanoparticles with glutamate for its delivery to and removal from brain nerve terminals

• Konstantin Paliienko,
• Artem Pastukhov,
• Michal Babič,
• Daniel Horák,
• Olga Vasylchenko and
• Tatiana Borisova

Beilstein J. Nanotechnol. 2020, 11, 1381–1393, doi:10.3762/bjnano.11.122

• ) equipped with a He–Ne laser LGN-111 (P = 25 mW, λ = 633 nm). A suspension of γ-Fe2O3 nanoparticles (1 mL) in the standard salt solution was placed to a cylindrical quartz cuvette of 10 mm in diameter, which was inserted into the laser correlation spectrometer. The measurement range of the instrument is

Magnetic-field-assisted synthesis of anisotropic iron oxide particles: Effect of pH

• Andrey V. Shibaev,
• Petr V. Shvets,
• Darya E. Kessel,
• Roman A. Kamyshinsky,
• Anton S. Orekhov,
• Sergey S. Abramchuk,
• Alexei R. Khokhlov and
• Olga E. Philippova

Beilstein J. Nanotechnol. 2020, 11, 1230–1241, doi:10.3762/bjnano.11.107

• HR800, Villeneuve-d'Ascq, France) equipped with 100× magnification lens. The copper substrates were dip-coated in the sample solutions and dried under ambient conditions. The measurements of the produced films were conducted at room temperature and atmospheric air. A He–Ne laser (λ = 632.8 nm) was used

Nanoparticles based on the zwitterionic pillar[5]arene and Ag⁺: synthesis, self-assembly and cytotoxicity in the human lung cancer cell line A549

• Dmitriy N. Shurpik,
• Denis A. Sevastyanov,
• Pavel V. Zelenikhin,
• Pavel L. Padnya,
• Vladimir G. Evtugyn,
• Yuriy N. Osin and
• Ivan I. Stoikov

Beilstein J. Nanotechnol. 2020, 11, 421–431, doi:10.3762/bjnano.11.33

• cuvettes. The instrument contains a 4 mW He–Ne laser operating at a wavelength of 633 nm and incorporates noninvasive backscatter optics (NIBS). The measurements were performed at the detection angle of 173° and the software automatically determined the measurement position within the quartz cuvette. The

pH-Controlled fluorescence switching in water-dispersed polymer brushes grafted to modified boron nitride nanotubes for cellular imaging

• Saban Kalay,
• Yurij Stetsyshyn,
• Volodymyr Donchak,
• Khrystyna Harhay,
• Ostap Lishchynskyi,
• Halyna Ohar,
• Yuriy Panchenko,
• Stanislav Voronov and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2019, 10, 2428–2439, doi:10.3762/bjnano.10.233

• measurements of the nanotubes were performed with a Zetasizer Nano ZS device (Malvern, USA) at 25 °C. The Nano ZS contains a 4 mW He–Ne laser operating at a wavelength of 633 nm and an avalanche photodiode detector. The scattered light was detected at an angle of 173°. The refractive index and absorption of

Mannosylated brush copolymers based on poly(ethylene glycol) and poly(ε-caprolactone) as multivalent lectin-binding nanomaterials

• Stefania Ordanini,
• Wanda Celentano,
• Anna Bernardi and
• Francesco Cellesi

Beilstein J. Nanotechnol. 2019, 10, 2192–2206, doi:10.3762/bjnano.10.212

• : -CH2CH2CH2-), 1.25–0.77 (m, 3H·(y + x), -CH3,backbone). Particle size measurements by DLS DLS analyses of polymers (1 mg/mL, filtered solutions with PTFE 0.45 µm filters) were performed using a Malvern Instrument Zetasizer Nano ZS instrument equipped with a 4 mW He–Ne laser operating at λ = 634 nm. Particle

Use of data processing for rapid detection of the prostate-specific antigen biomarker using immunomagnetic sandwich-type sensors

• Camila A. Proença,
• Tayane A. Freitas,
• Thaísa A. Baldo,
• Elsa M. Materón,
• Flávio M. Shimizu,
• Gabriella R. Ferreira,
• Frederico L. F. Soares,
• Ronaldo C. Faria and
• Osvaldo N. Oliveira Jr.

Beilstein J. Nanotechnol. 2019, 10, 2171–2181, doi:10.3762/bjnano.10.210

• working carbon electrodes combined with one pseudo-reference electrode (Ag/AgCl) and one auxiliary electrode (carbon). The microfluidic system was set up with an injection pump (NE-1000 programmable Single Syringe Pump, New Era Pump System, Farmingdale, USA) and an injection valve with a sample loop of

Liquid crystal tunable claddings for polymer integrated optical waveguides

• José M. Otón,
• Manuel Caño-García,
• Fernando Gordo,
• Eva Otón,
• Morten A. Geday and
• Xabier Quintana

Beilstein J. Nanotechnol. 2019, 10, 2163–2170, doi:10.3762/bjnano.10.209

• constructed. The cell consists of a LC (Merck MDA-98-1602, no = 1.52, ne = 1.78) sandwiched between the substrate containing the waveguides and an ITO-coated glass plate to provide a conductive layer for applying electric signals (Figure 8). The substrate Si wafer was employed as counter electrode. Si was

• structure with this alignment, one mode of light propagating through the waveguide would experience a cladding with a tunable refractive index in a range close to the LC birefringence ∆n = ne − no, where ne and no are the extraordinary and the ordinary index of the LC, respectively. In a second experimental

Ion mobility and material transport on KBr in air as a function of the relative humidity

• Dominik J. Kirpal,
• Korbinian Pürckhauer,
• Alfred J. Weymouth and
• Franz J. Giessibl

Beilstein J. Nanotechnol. 2019, 10, 2084–2093, doi:10.3762/bjnano.10.203

• interatomic spacing of a: The number of atoms at the step edge Ne can be described by If material transport is confined to the edges, then (see Equation 5): with Eb,e being the energy barrier height at the step edge. This yields a solution of the form with , and explains the increased decay of the structure

Green and scalable synthesis of nanocrystalline kuramite

• Andrea Giaccherini,
• Giuseppe Cucinotta,
• Stefano Martinuzzi,
• Enrico Berretti,
• Werner Oberhauser,
• Alessandro Lavacchi,
• Giovanni Orazio Lepore,
• Giordano Montegrossi,
• Maurizio Romanelli,
• Antonio De Luca,
• Massimo Innocenti,
• Vanni Moggi Cecchi,
• Matteo Mannini,
• Antonella Buccianti and
• Francesco Di Benedetto

Beilstein J. Nanotechnol. 2019, 10, 2073–2083, doi:10.3762/bjnano.10.202

• ][55]. Raman spectroscopy was performed with a He–Ne laser source emitting at 632.8 nm with a laser spot on the sample of about 10 μm2. The main reference for the positions of the Raman peaks is from the RRUFF database [56]. XAS measurements at Cu and Sn K-edge (8978.9 and 29200.1 eV, respectively

Gold-coated plant virus as computed tomography imaging contrast agent

• Alaa A. A. Aljabali,
• Mazhar S. Al Zoubi,
• Khalid M. Al-Batanyeh,
• Ali Al-Radaideh,
• Mohammad A. Obeid,
• Abeer Al Sharabi,
• Walhan Alshaer,
• Bayan AbuFares,
• Tasnim Al-Zanati,
• Murtaza M. Tambuwala,
• Naveed Akbar and
• David J. Evans

Beilstein J. Nanotechnol. 2019, 10, 1983–1993, doi:10.3762/bjnano.10.195

• recorded with the following settings: 20 mW He–Ne laser, λ0 = 780 nm, scattering angle θ = 90°, molar refractive index of 1.33; viscosity of 0.8872 at 25 °C; the attenuator was set up automatically and ranged between 6 to 9. Corresponding quartz cells were flushed with deionized water followed by a 1% (v/v

• –Einstein equation. Zeta potential measurements The zeta potential of the particles was measured on a Zetasizer™ NanoZS-90 (Malvern Instruments) equipped with a 4 mW, λ0 = 632 nm He–Ne laser operating with a detector angle of θ = 173° degree. The cell voltage of the instrument was fixed to 80 V during

Precise local control of liquid crystal pretilt on polymer layers by focused ion beam nanopatterning

• Maxim V. Gorkunov,
• Irina V. Kasyanova,
• Vladimir V. Artemov,
• Alena V. Mamonova and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2019, 10, 1691–1697, doi:10.3762/bjnano.10.164

• through the LC layer. Due to the LC birefringence, they acquire different optical paths: for the x-polarized state, and for the y-polarized state. For a relatively weak birefringence Δn = ne − no, we can write the measured phase retardation approximately as which is formally x-dependent. Substituting

Magnetic segregation effect in liquid crystals doped with carbon nanotubes

• Danil A. Petrov,
• Pavel K. Skokov,
• Alexander N. Zakhlevnykh and
• Dmitriy V. Makarov

Beilstein J. Nanotechnol. 2019, 10, 1464–1474, doi:10.3762/bjnano.10.145

• distortions in the orientational structure, the refractive index of the ordinary ray no remains unchanged, and the refractive index of the extraordinary ray ne will decrease and approach the value of no. Above the Fréedericksz transition the value of the effective refractive index neff depending on the angle

• the optical phase lag, in Equation 24 we change from integration over the coordinate ζ to integration over the angle φ using Equation 10, then Equation 24 can be written as Here, δ0 = 2πL(ne − no)/λ is the phase lag in the absence of a magnetic field, and the notation is introduced. In Equation 25

• passing through the NLC cell with a CNT impurity. For calculations we use the values of the refractive index of the liquid crystal 5CB (no = 1.53, ne = 1.71 for λ = 632.8 nm [45]), on the basis of which NLC–CNT mixtures can be prepared [24][32][50]. From Figure 7 it can be seen that in the initial planar

Molecular attachment to a microscope tip: inelastic tunneling, Kondo screening, and thermopower

• Rouzhaji Tuerhong,
• Mauro Boero and
• Jean-Pierre Bucher

Beilstein J. Nanotechnol. 2019, 10, 1243–1250, doi:10.3762/bjnano.10.124

• tunneling microscope (Modified Createc LT-STM) equipped with a vector magnetic field of 1 T. As described in [21], the Au(111) single crystal was cleaned by repeated cycles of Ne+ ion bombardment followed by thermal annealing at 800 K. The MnPc molecules were evaporated from an Al2O3 crucible heated by

Correlation of surface-enhanced Raman scattering (SERS) with the surface density of gold nanoparticles: evaluation of the critical number of SERS tags for a detectable signal

• Vincenzo Amendola

Beilstein J. Nanotechnol. 2019, 10, 1016–1023, doi:10.3762/bjnano.10.102

• micro-Raman instrument (CCD detector with 100 mm slits) on the TEM grids containing the AuNTs and using the 633 nm line of a He–Ne laser. The laser power at the entrance pupil of the microscope objective was 0.85 mW, corresponding to 0.65 mW at the output of the microscope objective (measured with a

Nanoscale optical and structural characterisation of silk

• Meguya Ryu,
• Reo Honda,
• Adrian Cernescu,
• Arturas Vailionis,
• Armandas Balčytis,
• Jitraporn Vongsvivut,
• Jing-Liang Li,
• Denver P. Linklater,
• Elena P. Ivanova,
• Vygantas Mizeikis,
• Mark J. Tobin,
• Junko Morikawa and
• Saulius Juodkazis

Beilstein J. Nanotechnol. 2019, 10, 922–929, doi:10.3762/bjnano.10.93

• (LC) retarder, which was inserted with its slow-axis perpendicular to the orientation of the silk fiber (see inset in Figure 3b). Using such a geometry, it is possible to compensate for the birefringence of the silk fibers, Δn ≡ ne − no > 0, with a phase delay imparted by the LC retarder. When the

An efficient electrode material for high performance solid-state hybrid supercapacitors based on a Cu/CuO/porous carbon nanofiber/TiO₂ hybrid composite

• Mamta Sham Lal,
• Thirugnanam Lavanya and
• Sundara Ramaprabhu

Beilstein J. Nanotechnol. 2019, 10, 781–793, doi:10.3762/bjnano.10.78

• and a transmission electron microscope (JEOL JEM 2100) operating at 200 kV. The crystalline structure was identified using a Rigaku Rintz Ultima X-ray diffraction unit. Raman spectra were analyzed by a LabRAM HP 800 UV with a 632 nm He–Ne laser as the excitation source in the range of 100–3000 cm−1 at

Site-controlled formation of single Si nanocrystals in a buried SiO₂ matrix using ion beam mixing

• Xiaomo Xu,
• Thomas Prüfer,
• Daniel Wolf,
• Hans-Jürgen Engelmann,
• Lothar Bischoff,
• René Hübner,
• Karl-Heinz Heinig,
• Wolfhard Möller,
• Stefan Facsko,
• Johannes von Borany and
• Gregor Hlawacek

Beilstein J. Nanotechnol. 2018, 9, 2883–2892, doi:10.3762/bjnano.9.267

• + or Ne+ ion beam mixing of Si into a buried SiO2 layer followed by thermally activated phase separation. Binary collision approximation and kinetic Monte Carlo methods are conducted to gain atomistic insight into the influence of relevant experimental parameters on the Si NC formation process. Energy

• -filtered transmission electron microscopy is performed to obtain quantitative values on the Si NC size and distribution in dependence of the layer stack geometry, ion fluence and thermal budget. Employing a focused Ne+ beam from a helium ion microscope, we demonstrate site-controlled self-assembly of

• single Si NCs. Line irradiation with a fluence of 3000 Ne+/nm2 and a line width of 4 nm leads to the formation of a chain of Si NCs, and a single NC with 2.2 nm diameter is subsequently isolated and visualized in a few nanometer thin lamella prepared by a focused ion beam (FIB). The Si NC is centered

Contactless photomagnetoelectric investigations of 2D semiconductors

• Marian Nowak,
• Marcin Jesionek,
• Barbara Solecka,
• Piotr Szperlich,
• Piotr Duka and
• Anna Starczewska

Beilstein J. Nanotechnol. 2018, 9, 2741–2749, doi:10.3762/bjnano.9.256

• occasional holes and cracks. The presence of single-layer graphene was confirmed by Raman spectroscopy using an NTEGRA Spectra (NT-NDT) device with a wavelength of 532 nm. The carrier mobility μe = 1256(25) cm2V−1s−1 and sheet carrier concentration ne = 4.65(6)·1016 m−2 in the graphene were determined using

• concentration (μe = 1256(25) cm2V−1s−1 and ne = 4.65(6)·1016 m−2 determined using Van der Pauw method). It should be underlined that one of the most important properties of graphene [33][34][35] and other 2D materials [2][36][37][38][39][40][41] is the strong electric field effect which leads to

Enhancement of X-ray emission from nanocolloidal gold suspensions under double-pulse excitation

• Wei-Hung Hsu,
• Frances Camille P. Masim,
• Armandas Balčytis,
• Hsin-Hui Huang,
• Tetsu Yonezawa,
• Aleksandr A. Kuchmizhak,
• Saulius Juodkazis and
• Koji Hatanaka

Beilstein J. Nanotechnol. 2018, 9, 2609–2617, doi:10.3762/bjnano.9.242

• permittivity of material, ν is the electron–ion collision rate, ω is the optical cyclic frequency at the wavelength of excitation, ne,a,cr are the electron, atom and critical densities, respectively. The imaginary part of the permittivity is given by: The threshold fluence for water to reach the ENZ state can

• plasma frequency ωp when the electron density, ne, is known. For instance, for gold ne = 5.9 × 1022 cm−3. The refractive index under ENZ conditions can be calculated as with use of Equation 2: Then AENZ = 4κ/[(κ + 1)2 + κ2] and the fluence threshold for the ENZ state is (Equation 3): with Δg = 6.2 eV

• calculated from the force F = Δp/Δt where the momentum in a medium of refractive index n of a laser pulse with energy E is p = nE/c[46]. When a light pulse of power P traverses from a low refractive index (n0 = 1, air) into a medium with larger refractive index (n1 = 1.33, water), momentum is gained and the

Pattern generation for direct-write three-dimensional nanoscale structures via focused electron beam induced deposition

• Lukas Keller and
• Michael Huth

Beilstein J. Nanotechnol. 2018, 9, 2581–2598, doi:10.3762/bjnano.9.240

• variable keeps track of the number of deposition events ne necessary to write the edge. ne represents the upper limit of variable ie that monitors the writing progress for the edge. The value for ne follows from the length of the edge le divided by the value of sF. Equation 2 provides an overview of the

• calibration experiment at a similar height z3D,i ≈ ζ would compensate for the reduced precursor coverage effect because ne = le/sF. Now we have For the set of values {(hi+1 − hi)/(z3D,i+1 − z3D,i)} vs the heights {z3D,i} obtained from the calibration experiment we perform a polynomial fit and obtain n ≤ 3

Self-assembled quasi-hexagonal arrays of gold nanoparticles with small gaps for surface-enhanced Raman spectroscopy

• Emre Gürdal,
• Simon Dickreuter,
• Fatima Noureddine,
• Pascal Bieschke,
• Dieter P. Kern and
• Monika Fleischer

Beilstein J. Nanotechnol. 2018, 9, 1977–1985, doi:10.3762/bjnano.9.188

• measured in a confocal Raman spectrometer (LabRam HR 800, Horia JobinYvon) using a 632.8 nm He–Ne-laser with a laser power of 50 mW and a 50× objective. The laser aperture was set to 1000 µm, the slit size to 200 µm and the grating had 1800 lines/mm, resulting in a spectral resolution of ≈2 cm−1. For all

Defect formation in multiwalled carbon nanotubes under low-energy He and Ne ion irradiation

• Santhana Eswara,
• Jean-Nicolas Audinot,
• Brahime El Adib,
• Maël Guennou,
• Tom Wirtz and
• Patrick Philipp

Beilstein J. Nanotechnol. 2018, 9, 1951–1963, doi:10.3762/bjnano.9.186

• Department, Luxembourg Institute of Science and Technology, 41 rue du Brill, L-4422 Belvaux, Luxembourg 10.3762/bjnano.9.186 Abstract The mechanical, structural, electronic and magnetic properties of carbon nanotubes can be modified by electron or ion irradiation. In this work we used 25 keV He+ and Ne+ ion

• thickness and ion species, the sputter yield is significantly higher for the bottom than the top side. For He+ and Ne+ irradiation, damage formation evolves differently, with a change in the trend of the ratio of D to G peak in the Raman spectra being observed for He+ but not for Ne+. This can be attributed

• -resolution imaging tool [32][33]. A He+ or Ne+ ion beam can be used to irradiated the samples with an impact energy in the range of 5 to 30 keV, either for imaging or nano-machining [34][35], or for doing both simultaneously [33]. For instance, the HIM has already been used for the imaging of graphene flakes

SO₂ gas adsorption on carbon nanomaterials: a comparative study

• Deepu J. Babu,
• Divya Puthusseri,
• Frank G. Kühl,
• Sherif Okeil,
• Michael Bruns,
• Manfred Hampe and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2018, 9, 1782–1792, doi:10.3762/bjnano.9.169

• carried out at 900 °C by passing ethene (200 sccm), hydrogen (800 sccm), argon (1200 sccm) and ppm-scale quantities of water vapor together for 15 min. Characterization techniques Raman measurements were performed using a Horiba Jobin Yvon, model HR 800 LabRAM high-resolution microscope using a He–Ne