Tunable high-quality-factor absorption in a graphene monolayer based on quasi-bound states in the continuum

• Jun Wu,
• Yasong Sun,
• Feng Wu,
• Biyuan Wu and
• Xiaohu Wu

Beilstein J. Nanotechnol. 2022, 13, 675–681, doi:10.3762/bjnano.13.59

• . TM polarized (the magnetic field is along the direction of the y-axis) monochromatic plane waves are incident from the substrate at an angle θ. In our simulation, we set d = 3.3 μm, w = 2.31 μm, h = 3.5 μm, nh = 3.48, ns = 1.45, and θ = 0.1°. The surface conductivity of graphene has intraband and

• Fermi level, ω is the angular frequency, e is the elementary charge, and τ is the carrier relaxation lifetime. In our simulation, the permittivity of the graphene monolayer is described by: where ε0 is the relative permittivity of vacuum, and hg is the thickness of the graphene, which is assumed to be

Fabrication and testing of polymer microneedles for transdermal drug delivery

• Vahid Ebrahiminejad,
• Zahra Faraji Rad,
• Philip D. Prewett and
• Graham J. Davies

Beilstein J. Nanotechnol. 2022, 13, 629–640, doi:10.3762/bjnano.13.55

• characteristics of the arrays using theoretical, experimental, and simulation approaches. The arrays are coated with fluorescein to simulate transdermal low molecular weight drug delivery. To study MN penetration, the replicated polymer MN arrays were applied on the skin with various application methods

• simulation model was performed using ANSYS (2020 R1, ANSYS, Canonsburg, Pennsylvania, USA) Explicit Dynamics. The skin was assumed to be comprised of three layers (1) stratum corneum, (2) dermis, and (3) hypodermis with 26 μm, 2 mm, and 1.1 mm thicknesses, respectively. An Ogden (first-order) model [32] was

• the elemental density, which in turn reduces the overall time step by increasing the time required for a sound wave to traverse the smallest elements. Table 1 summarizes the material properties used for the individual components in the insertion simulation. Results and Discussions Design and

Comparative molecular dynamics simulations of thermal conductivities of aqueous and hydrocarbon nanofluids

• Adil Loya,
• Antash Najib,
• Fahad Aziz,
• Asif Khan,
• Guogang Ren and
• Kun Luo

Beilstein J. Nanotechnol. 2022, 13, 620–628, doi:10.3762/bjnano.13.54

• thermophysical properties of nanofluids using a simulation environment. Moreover, this comparison introduces data on aqueous and nonaqueous suspensions in one study. Keywords: alkanes; aqueous solutions; CuO; hydrocarbon solutions; molecular dynamics simulation; nanoparticles; thermal conductivity

• study was carried out with different shapes (i.e., cylinder, platelet, and sphere) of nanoparticles (Cu/Al2O3 with ethylene glycol as the base fluid) using the finite element method (FEM) in MAPLE 18.0. For mathematical modelling and simulation of hybrid nanofluids, Shah et al. [33] considered a two

• molecules [1]. The molecular dynamics (MD) simulation method is a tool that has been used to effectively predict nanofluid thermal properties with relative accuracy [38][39][40][41][42]. The method relies on computationally solving basic equations of Newton’s laws of motion for interacting particles at the

Quantitative dynamic force microscopy with inclined tip oscillation

• Philipp Rahe,
• Daniel Heile,
• Reinhard Olbrich and
• Michael Reichling

Beilstein J. Nanotechnol. 2022, 13, 610–619, doi:10.3762/bjnano.13.53

• the tip movement can have critical consequences for data interpretation, especially for measurements on nanostructured surfaces exhibiting significant lateral force components. Inclination effects are illustrated by simulation results that resemble the representative experimental conditions of

• appropriate experimental procedures [22]. Simulation results for moving the tip along the inclined path during data acquisition and extracting the force along this path are presented in Figure 4d by the green curve. The force along this data recording path is correctly recovered as shown in Figure 4d where

A new method for obtaining the magnetic shape anisotropy directly from electron tomography images

• Cristian Radu,
• Ioana D. Vlaicu and
• Andrei C. Kuncser

Beilstein J. Nanotechnol. 2022, 13, 590–598, doi:10.3762/bjnano.13.51

• Avizo Amira or the more limited Tomviz and ImageJ, as well as software from TEM manufacturers, such as the visualizer Kay-JEOL). However, none of them is focused on answering the abovementioned issues, specific to magnetic nanoscale systems. On the other side, there are micromagnetic simulation software

Approaching microwave photon sensitivity with Al Josephson junctions

• Andrey L. Pankratov,
• Anna V. Gordeeva,
• Leonid S. Revin,
• Dmitry A. Ladeynov,
• Anton A. Yablokov and
• Leonid S. Kuzmin

Beilstein J. Nanotechnol. 2022, 13, 582–589, doi:10.3762/bjnano.13.50

• points at 300 and 600 mK agree well with the simulation results if the parameters for numerical calculations are 401 mK, Ic = 8.536 μA and 575 mK, Ic = 8.51 μA, respectively. The normal resistance and the capacitance are RN = 29 Ω and C = 2700 fF. It is interesting to note that even the curve for 50 mK

Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy

• Patrick Stohmann,
• Sascha Koch,
• Yang Yang,
• Christopher David Kaiser,
• Julian Ehrens,
• Jürgen Schnack,
• Niklas Biere,
• Dario Anselmetti,
• Armin Gölzhäuser and
• Xianghui Zhang

Beilstein J. Nanotechnol. 2022, 13, 462–471, doi:10.3762/bjnano.13.39

• scenario, the polymerization is proceeded by random dimerization of the neighboring monomers and a local dimerization event neither promotes nor inhibits dimerization of the neighboring sites. We performed a simple simulation assuming that one molecule can form covalent bonds with six neighboring molecules

• simulations. Figure 5d shows a typical structure of a TPT CNM, where pronounced valleys and hills in both height and lateral distance from each other can be clearly seen. In a simulation box containing 20 × 20 × 18 carbon atoms, the TPT CNM exhibits three subnanometer pores, corresponding to an areal density

• molecular dynamics. The LAMMPS package was employed and the EDIP as well as AIREBO carbon potentials were used depending on more technical simulation-specific parameters. As reported in the reference [71], the simulations included only carbon atoms. The modelling was achieved through the following steps: (1

A broadband detector based on series YBCO grain boundary Josephson junctions

• Egor I. Glushkov,
• Alexander V. Chiginev,
• Leonid S. Kuzmin and
• Leonid S. Revin

Beilstein J. Nanotechnol. 2022, 13, 325–333, doi:10.3762/bjnano.13.27

• –frequency characteristic, beam pattern, and fraction of the absorbed power in each Josephson junction were investigated. Based on the obtained results, a numerical simulation of one-dimensional arrays was carried out. The dc characteristics of the detector were calculated, that is, current–voltage

• the electromagnetic analysis and numerical simulation of the broadband detector based on a series of HTSC bicrystal Josephson junctions to maximize response, power dynamic range, and noise-equivalent power. Electromagnetic Simulation Figure 1a–c shows options for the geometry of a log-periodic antenna

• , additional expressions were used [23]. The tool used for the simulation was time domain solver of CST Microwave Studio. Two methods for calculating the receiving characteristics of the antenna were used. In the first method, microwave (MW) currents and voltages excited in each receiving element (port) were

The effect of metal surface nanomorphology on the output performance of a TENG

• Yiru Wang,
• Xin Zhao,
• Yang Liu and
• Wenjun Zhou

Beilstein J. Nanotechnol. 2022, 13, 298–312, doi:10.3762/bjnano.13.25

• %, and the improvement is not obvious (Figure 9). This is because the particle size distributions are too large. This can be seen intuitively in the COMSOL displacement simulation below in Figure 11. However, the charge density at the sharps tips is higher than that at the spherical strips, which is very

• types labeled “Struct. A” (pyramidal), “Struct. B” (strips), and “Struct. C” (spheroidal) (Figure 11). A COMSOL simulation can explain the differences in output performance caused by the different particle shapes. Taking pyramidal structures as an example, it can be seen in the simulated displacement

• of the output performance sinks. A simulation shows that nanoscale strips yield an optimal output performance, followed by pyramidal shapes. In addition, the electrodeposition rate of copper and the size of electrodeposited copper nanocrystals can be adjusted via the current density. The temperature

Investigation of a memory effect in a Au/(Ti–Cu)Ox-gradient thin film/TiAlV structure

• Damian Wojcieszak,
• Jarosław Domaradzki,
• Michał Mazur,
• Tomasz Kotwica and
• Danuta Kaczmarek

Beilstein J. Nanotechnol. 2022, 13, 265–273, doi:10.3762/bjnano.13.21

• investigations allowed us to conclude about the possible mechanism for the observed resistive switching mechanism. Keywords: gradient thin film; magnetron sputtering; memory effect; resistive switching; Introduction In recent years, significant development has been observed in design, simulation, manufacturing

• distribution profile of copper are presented. Experimental electrical measurements performed using DC simulation showed wide nonpinched hysteresis loops, indicating bipolar resistive switching properties. Additionally, the so-called forming process of switching properties has been observed for the first cycle

Surfactant-free syntheses and pair distribution function analysis of osmium nanoparticles

• Mikkel Juelsholt,
• Jonathan Quinson,
• Emil T. S. Kjær,
• Baiyu Wang,
• Rebecca Pittkowski,
• Susan R. Cooper,
• Tiffany L. Kinnibrugh,
• Søren B. Simonsen,
• Luise Theil Kuhn,
• María Escudero-Escribano and
• Kirsten M. Ø. Jensen

Beilstein J. Nanotechnol. 2022, 13, 230–235, doi:10.3762/bjnano.13.17

• or decahedral motifs are often observed for metals with normally close-packed structures [35]. By using the atomic simulation environment (ASE) module [36] and the cluster-mining approach developed by Banerjee et al. [35] we screened a large number of metal NP clusters, including hexagonal close

Theoretical understanding of electronic and mechanical properties of 1T′ transition metal dichalcogenide crystals

• Seyedeh Alieh Kazemi,
• Sadegh Imani Yengejeh,
• Vei Wang,
• William Wen and
• Yun Wang

Beilstein J. Nanotechnol. 2022, 13, 160–171, doi:10.3762/bjnano.13.11

• comparison with 2H TMD crystals and 1T′ monolayers. Computational Details All DFT computations were performed by using the Vienna ab initio simulation package (VASP) code with the projector augmented wave (PAW) method [34][35][36]. The Perdew–Burke–Ernzehof (PBE) exchange–correlation functional at the

Nanoscale friction and wear of a polymer coated with graphene

• Robin Vacher and
• Astrid S. de Wijn

Beilstein J. Nanotechnol. 2022, 13, 63–73, doi:10.3762/bjnano.13.4

• the nanoscale. We show that graphene protects the polymer substrate from wear and identify the mechanism of this protection. We show that crumpling of the graphene has an impact on the friction. In the next section we first describe the simulation setup. Then we move on to discussing our simulations

• of depositing, indenting, and sliding on graphene. In the final section, we draw some conclusions. Simulation Setup We simulate a slab of polyvinyl alcohol (PVA) coated with a single layer of graphene and a counterbody representing an AFM tip consisting of silicon. The simulations were performed

• using LAMMPS [29]. We use the same simulation setup for the polymer as in our previous work [23]. We summarise this setup below. Interaction potentials PVA is described using a united-atom force field developed by Müller-Plathe and co-workers [30]. Each polymer particle represents a monomer of one

Effect of lubricants on the rotational transmission between solid-state gears

• Huang-Hsiang Lin,
• Jonathan Heinze,
• Alexander Croy,
• Rafael Gutiérrez and
• Gianaurelio Cuniberti

Beilstein J. Nanotechnol. 2022, 13, 54–62, doi:10.3762/bjnano.13.3

• formation process between gears. Keywords: lubricants; MD simulation; rotational transmission; solid-state gears; Introduction In mechanical systems, lubrication is the most common way to reduce friction and wear [1][2][3][4]. The idea of lubricants is preventing direct contact between surfaces to avoid

• fluid. One obtains several fluid properties such as pressure, velocity, shear stress, density and strain rate. In the case of the gear–oil–gear system, several studies based on the CFD simulation have been reported [11][12][13][14][15][16][17][18]. However, most of the simulations for this type of

• . Methodology In this section, we introduce how the system is defined and we specify the simulation protocols used in the MD simulations. Setup To start our study of how different lubricants can affect the rotational transmission at the nanoscale, we consider the system shown in Figure 1. First, we design two

Sputtering onto liquids: a critical review

• Anastasiya Sergievskaya,
• Adrien Chauvin and
• Stephanos Konstantinidis

Beilstein J. Nanotechnol. 2022, 13, 10–53, doi:10.3762/bjnano.13.2

Heating ability of elongated magnetic nanoparticles

• Elizaveta M. Gubanova,
• Nikolai A. Usov and
• Vladimir A. Oleinikov

Beilstein J. Nanotechnol. 2021, 12, 1404–1412, doi:10.3762/bjnano.12.104

• of magnitude with an increase in the volume fraction of nanoparticles in a cluster in the range of 0.04–0.2. Keywords: elongated magnetic nanoparticles; magnetic hyperthermia; numerical simulation; specific absorption rate; Introduction Magnetic nanoparticle assemblies have great potential for the

• with an increase in the particle volume fraction in a cluster in the range η = 0.04–0.2. Numerical Simulation In this work the magnetic properties of various assemblies of elongated spheroidal magnetite nanoparticles with different aspect ratios a/b > 1 are studied by means of numerical simulation. It

• cubic [25] magnetic anisotropy showed the existence of an interval of optimal nanoparticle diameters where the SAR of the assembly reaches a maximum at a given frequency and amplitude of an ac magnetic field. In this work, using numerical simulation, similar results were obtained for spheroidal

Design aspects of Bi₂Sr₂CaCu₂O_8+δ THz sources: optimization of thermal and radiative properties

• Mikhail M. Krasnov,
• Natalia D. Novikova,
• Roger Cattaneo,
• Alexey A. Kalenyuk and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2021, 12, 1392–1403, doi:10.3762/bjnano.12.103

• mesa size, as well as whisker and electrode widths are λ1/8 = 37.5 μm; the crystal height is λ1/10 = 30 μm; mesa and whisker heights and the electrode thickness are λ1/100 = 3 μm; the simulation sphere radius is R = 2λ1 and the perfectly matching layer thickness is 0.2λ1. The sizes and parameters are

• mesa. The same color scale is used, indicated in the middle panel of Figure 6b. The rightmost panels represent far-field radiation patterns (directionality diagrams) of the electric field amplitude outside the simulation sphere. From comparison of the middle panels in Figure 6a,b it can be seen that

• device. Left panels show sketches of devices; middle panels – electric field amplitudes in the x-z cross-section through the mesa; right panels represent radiation patterns for the electric field amplitude in the far-field (outside the simulation sphere). Note a strong field concentration between the

Cantilever signature of tip detachment during contact resonance AFM

• Devin Kalafut,
• Ryan Wagner,
• Maria Jose Cadena,
• Anil Bajaj and
• Arvind Raman

Beilstein J. Nanotechnol. 2021, 12, 1286–1296, doi:10.3762/bjnano.12.96

• photodiode amplitude signal in units of μrad to a numerical simulation of the cantilever response driven by moment couples of different magnitudes. Figure 1c shows the maximum deflection of the cantilever about static equilibrium for the numerical simulations. The dashed grey line in this Figure indicates

• measurements. We also explore the aggregate numerical simulation data of Figure 1 by way of the phase space representation in Figure 3. The phase space has as many dimensions as state variables, but we restrict our viewing to the dominant contributors of the first three basis function modal coordinates

• Figure 1, the system was simulated at a selected bending moment couple drive amplitude until steady-state, at which point the frequency was stepped incrementally up or down using final state variable values from the previous simulation point as initial conditions. A fast Fourier transform of the steady

Nonmonotonous temperature dependence of Shapiro steps in YBCO grain boundary junctions

• Leonid S. Revin,
• Dmitriy V. Masterov,
• Alexey E. Parafin,
• Sergey A. Pavlov and
• Andrey L. Pankratov

Beilstein J. Nanotechnol. 2021, 12, 1279–1285, doi:10.3762/bjnano.12.95

• at low temperatures. Nevertheless, the simulation qualitatively follows the experimental dependence within the entire temperature range. The obtained effect of the optimum in the JJ response is associated with a simultaneous change of several parameters when the temperature changes. For a qualitative

A review on slip boundary conditions at the nanoscale: recent development and applications

• Ruifei Wang,
• Jin Chai,
• Bobo Luo,
• Xiong Liu,
• Jianting Zhang,
• Min Wu,
• Mingdan Wei and
• Zhuanyue Ma

Beilstein J. Nanotechnol. 2021, 12, 1237–1251, doi:10.3762/bjnano.12.91

• force [39][40][41][42]. However, compared with experimental methods, numerical simulations, such as the lattice Boltzmann method and molecular dynamics (MD) simulation, are more attractive in many aspects. First, numerical simulations can readily reach the system sizes and timescales of practical

• interaction energy, and water slippage (or friction coefficient) may also not have a one-to-one correspondence between each other [67][68][69]. Contrary to the conventional wisdom, where slip boundary conditions are not valied for water slippage on hydrophilic surfaces, some simulation observations show that

• length correspondingly decreases [23][46]. Joly et al. proposed an approximate model to describe the relationship between the slip length and surface charge density. They validated the model by using a MD simulation with an ionized solution system represented by models of ideal solvents and ions [46

The effect of cobalt on morphology, structure, and ORR activity of electrospun carbon fibre mats in aqueous alkaline environments

• Markus Gehring,
• Tobias Kutsch,
• Osmane Camara,
• Alexandre Merlen,
• Hermann Tempel,
• Hans Kungl and
• Rüdiger-A. Eichel

Beilstein J. Nanotechnol. 2021, 12, 1173–1186, doi:10.3762/bjnano.12.87

• further improved by applying a copper tape connecting the sample and the graphite tape. To identify the particles decorating the nanofibres, EDX was performed using an Octane Super EDX detector (EDAX). The programme “monte CArlo SImulation of electroN trajectory in sOlids” (CASINO) [23], which simulates

Irradiation-driven molecular dynamics simulation of the FEBID process for Pt(PF₃)₄

• Alexey Prosvetov,
• Alexey V. Verkhovtsev,
• Gennady Sushko and
• Andrey V. Solov’yov

Beilstein J. Nanotechnol. 2021, 12, 1151–1172, doi:10.3762/bjnano.12.86

• presents a detailed computational protocol for the atomistic simulation of formation and growth of metal-containing nanostructures during focused electron beam-induced deposition (FEBID). The protocol is based upon irradiation-driven molecular dynamics (IDMD), a novel and general methodology for computer

• . The methodology can also be adjusted to simulate the nanostructure formation by other nanofabrication techniques using electron beams, such as direct electron beam lithography. In the present study, the methodology is applied to the IDMD simulation of the FEBID of Pt(PF3)4, a widely studied precursor

• nanostructures. The analysis of the simulation results provides spatially resolved relative metal content, height, and growth rate of the deposits, which represents valuable reference data for the experimental characterization of the nanostructures grown by FEBID. Keywords: focused electron beam-induced

Criteria ruling particle agglomeration

• Dieter Vollath

Beilstein J. Nanotechnol. 2021, 12, 1093–1100, doi:10.3762/bjnano.12.81

• of an agglomerated ensemble, that is, an exponential function characterized by two parameters. In this context, it is important to realize that one has to take care of fluctuations of the entropy. Keywords: agglomeration; enthalpy; entropy; simulation; surface energy; van der Waals interaction

• must not be exceeded. It is necessary to distinguish between the entropy fluctuation phenomenon described by Mishin and that explained earlier by Crooks [16] for small systems. Results Results of the entropy simulation As described in the previous chapter, the maximum entropy principle gives clear

• , together with the evaluation of the simulation calculations are given in Table 1. To improve readability, in this table, instead of ncoll the parameter a = ncoll/Ntot is given. This table compares the results obtained from Equation 11 and from simulations. As fluctuation processes influence the simulation

A new method for obtaining model-free viscoelastic material properties from atomic force microscopy experiments using discrete integral transform techniques

• Berkin Uluutku,
• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2021, 12, 1063–1077, doi:10.3762/bjnano.12.79

• single Voigt unit in series with a spring. Details about the simulation and the material parameters can be found in the Methods section. Linear ramp stress is applied to the material, from which the corresponding strain is calculated. This calculation gives the stress vs strain as a time-dependent array

• illustrated in Figure 5 for the data provided in Figure 4. Furthermore, although we have used a viscoelastic model to generate the material behavior for our simulation, the calculated retardance and relaxance (Figure 4 and Figure 5) are directly derived from the response of the material and are model-free

• simulation provides a fair approximation according to Figure 6. As the value of z increases along the real axis, the value of the retardance approaches the theoretical glassy compliance, which refers to the material’s infinitely short-timescale response (i.e., instantaneous response), and which is

Is the Ne operation of the helium ion microscope suitable for electron backscatter diffraction sample preparation?

• Annalena Wolff

Beilstein J. Nanotechnol. 2021, 12, 965–983, doi:10.3762/bjnano.12.73

• concentration and would be sufficiently high to form a Cu3Ga phase. This value represents an average and does not take random elements of the Ga distribution into account. The simulation results suggest that phase transformations are not likely to occur homogeneously throughout the sample but rather are

• the steady-state condition is reached later, allowing for a higher Ga impurity implantation concentration. The experimental result is in good agreement with the theoretical prediction from the Monte Carlo simulation and subsequent calculations. The Cu3Ga phase-transformed regions are larger for the

• SRIM simulation suggested that each copper atom is displaced around 22 times during the polishing process. A high enough Cu atom as well as Ga ion mobility is likely to move ions as well as displaced Cu atoms into grain boundaries. Grain boundaries can facilitate transport deeper into the material and