Comparing the performance of single and multifrequency Kelvin probe force microscopy techniques in air and water

• Jason I. Kilpatrick,
• Emrullah Kargin and
• Brian J. Rodriguez

Beilstein J. Nanotechnol. 2022, 13, 922–943, doi:10.3762/bjnano.13.82

• resolution [13][15][16][17][18][19]. These advances have enabled investigations mapping light-induced surface potential dynamics [20], ferroelectric domains [19], individual quantum dots [21][22], and even submolecular charge distributions [23][24][25][26][27]. These applications demonstrate that KPFM is

Ultrafast signatures of magnetic inhomogeneity in Pd_1−xFe_x (x ≤ 0.08) epitaxial thin films

• Andrey V. Petrov,
• Sergey I. Nikitin,
• Lenar R. Tagirov,
• Amir I. Gumarov,
• Igor V. Yanilkin and
• Roman V. Yusupov

Beilstein J. Nanotechnol. 2022, 13, 836–844, doi:10.3762/bjnano.13.74

• magnetic inhomogeneities in thin films. Individual constituents can be characterized by specific relaxation components that can be used to detect magnetic inhomogeneities and track their evolution. In addition, the peculiarities of the magnetization dynamics in magnetically inhomogeneous systems themselves

• are of interest. In our recent work, using the example of a thin epitaxial film of Pd0.94Fe0.06, it was demonstrated [37] that the dynamics of the reflection coefficient and the angle of rotation of the polarization plane in magneto-optical Kerr effect (MOKE) measurements after a photoexcitation with

• angles were ≈2° and ≈18°. The relaxation of the electronic subsystem was monitored by the relative change in the reflection coefficient (∆R/R). Ultrafast dynamics of the magnetization was analyzed by the deviation of the angle of rotation of the polarization plane of the probing light from the

Modeling a multiple-chain emeraldine gas sensor for NH₃ and NO₂ detection

• Hana Sustkova and
• Jan Voves

Beilstein J. Nanotechnol. 2022, 13, 721–729, doi:10.3762/bjnano.13.64

• gradient approximated (GGA) Perdew–Burke–Ernzerhof (PBE) exchange–correlation functional was used. Guo et al. [5] investigated the graphene/polyaniline adsorption energy of NH3, CO, NO, and H2 using DFT and molecular dynamics computations. From this, graphene/PANI is highly sensitive to NH3 in comparison

• chosen fixed positions of ammonia and nitrogen dioxide molecules. We have computed the local energy minima through molecular dynamics, which results in the optimized position and orientation of the gas molecule. The spatial orientation of the gas molecules was estimated by these optimizations. Next, one

• as well. The I–V characteristics were computed for several molecule positions near the doped and near the undoped nitrogen atoms, see above. The molecule orientation was estimated through molecular dynamics optimization. The resistance from the linear part of the I–V characteristics was used to

Direct measurement of surface photovoltage by AC bias Kelvin probe force microscopy

• Masato Miyazaki,
• Yasuhiro Sugawara and
• Yan Jun Li

Beilstein J. Nanotechnol. 2022, 13, 712–720, doi:10.3762/bjnano.13.63

• . Indeed, there remains an issue that the modulation frequency has the constraint of a transfer function of cantilever dynamics and the bandwidth of the PLL. We believe that this issue will be solved by future work such as using a heterodyne detection scheme [65][66][67]. It is noted that AC-KPFM observes

• it would be useful to operate AC-KPFM with a heterodyne detection scheme [65][66][67] in order to reduce a photothermal effect on the cantilever dynamics [68][69] and measure the fast SPV phenomena. The AC-KPFM method is utilized not only for SPV measurements, but also for direct measurements of

Design and selection of peptides to block the SARS-CoV-2 receptor binding domain by molecular docking

• Kendra Ramirez-Acosta,
• Ivan A. Rosales-Fuerte,
• J. Eduardo Perez-Sanchez,
• Alfredo Nuñez-Rivera,
• Josue Juarez and
• Ruben D. Cadena-Nava

Beilstein J. Nanotechnol. 2022, 13, 699–711, doi:10.3762/bjnano.13.62

• variants of SARS-CoV-2. This research work will be focused on the molecular docking of peptides by molecular dynamics, in addition to an analysis of the possible interaction of these peptides with physiological proteins. This methodology could be extended to design peptides that are active against other

A superconducting adiabatic neuron in a quantum regime

• Marina V. Bastrakova,
• Dmitrii S. Pashin,
• Dmitriy A. Rybin,
• Andrey E. Schegolev,
• Nikolay V. Klenov,
• Igor I. Soloviev,
• Anastasiya A. Gorchavkina and
• Arkady M. Satanin

Beilstein J. Nanotechnol. 2022, 13, 653–665, doi:10.3762/bjnano.13.57

• , Russia Federal State Unitary Enterprise All-Russia Research Institute of Automatics named after N.L. Dukhov, 101000 Moscow, Russia 10.3762/bjnano.13.57 Abstract We explore the dynamics of an adiabatic neural cell of a perceptron artificial neural network in a quantum regime. This mode of cell operation

• work, we account for this by considering the neuron cell operation in a quantum regime. We investigate the dynamics of this cell in search of conditions that provide the required sigmoid activation function (conversion of the input magnetic flux into the average output current), suitable for the

• the dynamics of the neuron. The range of the operating parameters for the proposed neuron circuit under the action of unipolar magnetic flux pulses is found. Finally, the influence of the dissipation on the features of the dynamic processes and characteristics of the cell is revealed. Methods Neuron

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

• 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

• BD Ultra-Fine™ 4 mm Pen Needle on porcine back skin, along with (3) Explicit Dynamics simulation of single MN insertion on a three-layered skin model. The comparisons between the results found for insertion force and quasi-static buckling test showed sufficient margins of safety (SM ≫ 1), indicating

• recorded during insertion based on c) FEA Explicit Dynamics simulation, and d) in vitro experiment using a BD Ultra-Fine™ 4 mm Pen Needle on porcine skin. Confocal images of cryo-sectioned porcine back skin showing MN array penetration: a) control test without MNs or fluorescein solution, b) MN array patch

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

• ., alkane) the thermal conductivity was increased three times (from 0.1 to 0.4 W·m−1·K−1). This approach to determine the thermal conductivity of metal oxide nanoparticles in aqueous and nonaqueous fluids using visual molecular dynamics and interactive autocorrelations demonstrate a great tool to quantify

• 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

• 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

• displacement qs with turning points qs + A and qs − A (Figure 1d). The momentary tip position at time t can either be described as the displacement q(t) or as the position zts(t), whereby the lower turning point is the point of strongest tip–surface interaction. While the tip position and sensor dynamics can

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

• samples in a single-shot regime and outline the junction parameter range where approaching single photon sensitivity is possible. Results and Discussion In this section, we describe our experimental setup, as well as the measurement results and comparison with theory. To study the dynamics of a SIS tunnel

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

• with a scanning tunneling microscope. As the irradiation dose was increased, the cross-linked regions continued to grow and a large number of subnanometer voids appeared. Their equivalent diameter is 0.5 ± 0.2 nm and the areal density is ≈1.7 × 1017 m−2. Supported by classical molecular dynamics

• cross-linked regions appear darker than the structurally ordered domains. At high doses, subnanometer-sized voids are formed preferably in regions of lower structural order and lower density in the monolayer. The formation of carbon nanomembranes was also modeled using classical molecular dynamics

• were analyzed by using an empirical fit. The lateral distribution of subnanometer voids was analyzed by partitioning the surface area into small segments and counting the number of voids in each segment. Classical molecular dynamics simulations The formation of a CNM was modelled using classical

Electrostatic pull-in application in flexible devices: A review

• Teng Cai,
• Yuming Fang,
• Yingli Fang,
• Ruozhou Li,
• Ying Yu and
• Mingyang Huang

Beilstein J. Nanotechnol. 2022, 13, 390–403, doi:10.3762/bjnano.13.32

• et al. [33] used molecular dynamics to compare the adsorption energies of GR-Au and GR-GR structures. The GR-GR structure has a higher adsorption energy of 307 mJ/m2. Mizuta et al. [7][35] assumed that the use of a GR-GR electrode structure could avoid the uncontrollable microscale interactions

Controllable two- and three-state magnetization switching in single-layer epitaxial Pd_1−xFe_x films and an epitaxial Pd_0.92Fe_0.08/Ag/Pd_0.96Fe_0.04 heterostructure

• Igor V. Yanilkin,
• Amir I. Gumarov,
• Gulnaz F. Gizzatullina,
• Roman V. Yusupov and
• Lenar R. Tagirov

Beilstein J. Nanotechnol. 2022, 13, 334–343, doi:10.3762/bjnano.13.28

• ): 0 Oe → −36 Oe. In both cases, on a time scale of approx. 1000 s, there are no noticeable changes in the magnetic moment of the steady states of the heterostructure. This is fundamentally different from the dynamics of the magnetization of the polycrystalline Pd0.99Fe0.01 film, in which significant

Thermal oxidation process on Si(113)-(3 × 2) investigated using high-temperature scanning tunneling microscopy

• Hiroya Tanaka,
• Shinya Ohno,
• Kazushi Miki and
• Masatoshi Tanaka

Beilstein J. Nanotechnol. 2022, 13, 172–181, doi:10.3762/bjnano.13.12

• ) has been used as the ideal tool to investigate reaction dynamics on surfaces. In our previous studies, we applied our VT-STM to investigate hydrogen diffusion [5] and titanium silicide formation [6] on Si(001). In our previous studies of oxidation on Si(113), we investigated the electronic states of

• ) substrate dramatically, so that it was close to that of Si(001) [1]. To gain insight into the origin of this remarkable reduction in Dit, it is necessary to understand the dynamic processes that occur during thermal oxidation more precisely. To this end, we observed the reaction dynamics during thermal

• towards a thin film regime. Conclusion We investigated three oxidation growth modes – oxidation, etching, and transition modes – in the third of which both oxidation and etching occur. Reaction dynamics in the oxidation of Si(113)-(3 × 2) was observed in real time using VT-STM. Nucleation of the oxide and

Influence of magnetic domain walls on all-optical magnetic toggle switching in a ferrimagnetic GdFe film

• Rahil Hosseinifar,
• Evangelos Golias,
• Ivar Kumberg,
• Quentin Guillet,
• Karl Frischmuth,
• Sangeeta Thakur,
• Mario Fix,
• Manfred Albrecht,
• Florian Kronast and
• Wolfgang Kuch

Beilstein J. Nanotechnol. 2022, 13, 74–81, doi:10.3762/bjnano.13.5

• radiation beamtime. Funding This work was supported by the Deutsche Forschungsgemeinschaft via the CRC/TRR 227 “Ultrafast Spin Dynamics”, project A07.

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

• challenging problem due to the complex viscoelastic properties and structure. Using molecular dynamics simulations, we investigate how a graphene sheet on top of the semicrystalline polymer polyvinyl alcohol affects the friction and wear. Our setup is meant to resemble an AFM experiment with a silicon tip. We

• the polymer chains and reduces the indentation depth. Keywords: friction; graphene; molecular dynamics; polymer; Introduction Graphene is a two dimensional material that has remarkable properties, both electronic [1][2] and mechanical [3][4]. Even before anything was known about graphene, the

• . [27][28] show that graphene has a strong effect on the structure and dynamics of the polymer chains near the interface. In this work, we aim to develop our understanding of the frictional behavior of a polymer coated with graphene by using molecular dynamics simulations of a single sliding asperity at

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

• are taken into account due to high pressure at intermediate sliding velocities. On the macroscopic scale, the hydrodynamics of the fluid can be analyzed by computational fluid dynamics (CFD) [6][7], which is based on solving the Navier–Stokes equation [8][9] or Reynold equation [10] for the thin-film

• and velocity distribution are not well defined and one has to resort to an atomistic description, for example, via molecular dynamics (MD) simulations. Also, the contact mechanics at the nanoscale is very different from the macroscopic case since specific pair interactions have to be taken into

• only for better visibility since the actual thickness of the lubricant layer is 5.0–5.5 nm to ensure that the gears are immersed. Finally, the whole system is optimized by using the conjugate gradient method implemented within LAMMPS [58]. Molecular dynamics In this study, we use LAMMPS to perform the

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

• anisotropy constant, Kef ≈ KSh, determines the characteristic value of the reduced energy barrier between potential wells. The latter is equal in order of magnitude to σ = KefV/kBT, where kB is the Boltzmann constant and T is the absolute temperature. The dynamics of the unit magnetization vector of a

• field, is very small. At the same time, at small values of this parameter, σ ≪ 1, the dynamics of the unit magnetization vector is determined by thermal fluctuations, and the effect of the ac magnetic field is insignificant. Therefore, at fixed amplitude of the ac magnetic field, with increase in 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

• to improve their measurements. We shed light on this issue by deliberately pushing both our experimental equipment and numerical simulations to the point of tip–sample detachment to explore cantilever dynamics during a useful and observable threshold feature in the measured response. Numerical

• simulations of the analytical model allow for extended insight into cantilever dynamics such as full-length deflection and slope behavior, which can be challenging or unobtainable in a standard equipment configuration. With such tools, we are able to determine the cantilever motion during detachment and

• nonlinear response feature to the onset of tip–sample detachment in our numerical simulations to confirm the conclusions from prior works [26][27][28]. The simulations allow for deeper insight into cantilever dynamics during the interaction between the AFM probe tip and the sample, which in turn allow us to

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

• ; Shapiro steps; temperature dependence; YBaCuO Josephson junction; Introduction High-temperature superconducting (HTSC) Josephson junctions (JJs) are of great interest since many physical properties can be observed in dynamics during the changing the temperature within a wide range from nitrogen

• increases, and for 20 K, in the general case, Equation 1 becomes invalid, that is, the dynamics of the spatial distribution of the phase and the magnetic field inside the junction becomes important [39][40][41]. In the case of long JJs it is necessary to consider the sine-Gordon equation, taking into

• account the non-uniform distribution of currents flowing through the barrier, which is typical for bicrystal junctions [28][42][43]. However, if the junction length is of the order of the kink size and there is no external magnetic field, the long junction dynamics is close to that of a short one [39] and

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

• Beskok compared a slip-modified theoretical model with the molecular dynamics simulation results. They found that the slip enhancement in the electro-osmotic flow is independent of the channel height, which can provide a theoretical basis for membrane fabrication of electrically assisted nanofiltration

Impact of electron–phonon coupling on electron transport through T-shaped arrangements of quantum dots in the Kondo regime

• Patryk Florków and
• Stanisław Lipiński

Beilstein J. Nanotechnol. 2021, 12, 1209–1225, doi:10.3762/bjnano.12.89

• Nph is given by the Bose–Einstein distribution. In this approach the electron and phonon dynamics become decoupled. This approximation, which is widely used in literature [49][58][59][70][71][72], predicts the exponential suppression of the tunneling amplitudes (Franck–Condon (F–C)-type suppression

• state and double or fourfold occupied states become degenerate. The low-temperature dynamics is then described only by charge fluctuations, that is, flips of charge pseudospin (charge Kondo effect). Of special interest are the effective fluctuations between degenerate empty and fully occupied states

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

• deposition; irradiation-driven molecular dynamics; irradiation-induced chemistry; platinum nanostructures; reactive force fields; Introduction The controllable fabrication of nanostructures with nanoscale resolution remains a considerable scientific and technological challenge [1]. To address this challenge

• dynamics (IDMD) [13], a novel and general methodology for computer simulations of irradiation-driven transformations of complex molecular systems. This approach overcomes the limitations of previously used computational methods and describes FEBID-based nanostructures at the atomistic level by accounting

Self-assembly of amino acids toward functional biomaterials

• Huan Ren,
• Lifang Wu,
• Lina Tan,
• Yanni Bao,
• Yuchen Ma,
• Yong Jin and
• Qianli Zou

Beilstein J. Nanotechnol. 2021, 12, 1140–1150, doi:10.3762/bjnano.12.85

• ]. Although traditional materials provide good structural analogues for native bone and surrounding tissue, they are difficult to mimic the dynamics and complexity of the natural environment [9]. Therefore, it is necessary to develop a new generation of biomaterials to improve strategies for natural tissue

• phenylketonuria. Bera et al. [37] studied the effect of chiral on aromatic amino acid self-assembly. They found that the hybrid ᴅʟ system (racemate) alters the morphology and dynamics of the assemblies. For example, either ʟ-phenylalanine or ᴅ-phenylalanine can form amyloid fibers, but the ᴅʟ system shows a