Pull-off and friction forces of micropatterned elastomers on soft substrates: the effects of pattern length scale and stiffness

• Peter van Assenbergh,
• Marike Fokker,
• Julian Langowski,
• Jan van Esch,
• Marleen Kamperman and
• Dimitra Dodou

Beilstein J. Nanotechnol. 2019, 10, 79–94, doi:10.3762/bjnano.10.8

• the micropattern. The PVA substrates have some dissipative properties (dissipation factors of PVA-12: tan δ = 0.05; PVA-18: tan δ = 0.07), which might contribute to the resultant pull-off force as well. Given the low value of these dissipation factors, we doubt whether damping plays a significant role

Polarization-dependent strong coupling between silver nanorods and photochromic molecules

• Gwénaëlle Lamri,
• Alessandro Veltri,
• Jean Aubard,
• Pierre-Michel Adam,
• Nordin Felidj and
• Anne-Laure Baudrion

Beilstein J. Nanotechnol. 2018, 9, 2657–2664, doi:10.3762/bjnano.9.247

• than the sum of their line widths [19]. This condition implies that the Rabi oscillation period is shorter than the damping time of the plasmon and of the organic exciton. In our case, the fitted decomposition of the curves into two Lorentzian curves (inset of the Figure 2b) leads to an energy

• equal to 132 and 235 nm, leading to linewidths of 655 and 697 meV. This difference in the hybrid mode linewidths has already been observed for a gold nanogroove arrays coated with a J-aggregate dye film [25]. In this work, they observed different damping rates for the hybrid modes attributed to the

• interplay between the coherent dipole coupling between exciton and plasmon and the incoherent exchange of photon energy between both systems. This can happen when the damping of both separate oscillators is different, which is our case with the plasmonic resonance and the MC molecular exciton. The large

Nanoantenna structures for the detection of phonons in nanocrystals

• Alexander G. Milekhin,
• Sergei A. Kuznetsov,
• Ilya A. Milekhin,
• Larisa L. Sveshnikova,
• Tatyana A. Duda,
• Ekaterina E. Rodyakina,
• Alexander V. Latyshev,
• Volodymyr M. Dzhagan and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2018, 9, 2646–2656, doi:10.3762/bjnano.9.246

• structure, while a Drude model with linear plasma and damping frequencies of 72,500 cm−1 and 216 cm−1, respectively, was applied to correctly describe the frequency response of gold [12]. To avoid undesirable computational effects arising from wave interference in the Si wafer of finite thickness, the Si

Friction reduction through biologically inspired scale-like laser surface textures

• Johannes Schneider,
• Vergil Djamiykov and
• Christian Greiner

Beilstein J. Nanotechnol. 2018, 9, 2561–2572, doi:10.3762/bjnano.9.238

• chosen that resulted in regular, elliptical protrusions, lowering friction compared to an untextured control sample [24]. In an approach resulting in surface textures much closer to the natural example, Baum et al. showed that variations in the effective elastic modulus (therefore allowing for damping

Effective sensor properties and sensitivity considerations of a dynamic co-resonantly coupled cantilever sensor

• Julia Körner

Beilstein J. Nanotechnol. 2018, 9, 2546–2560, doi:10.3762/bjnano.9.237

• described as a coupled harmonic oscillator, consisting of a damping element d1,2, spring k1,2 and effective mass m1,2 for each subsystem. Please note that m1,2 still denotes the effective mass but the subscript eff was omitted to keep the descriptions short. The model furthermore allows to study external

• results in a sixth degree polynomial expression that can only be solved numerically. Consequently, for an estimate of the resonance frequencies, we consider the model from Figure 1c without the damping elements d1,2. The validity of this assumption is supported by comparison of simulation results for the

• damped and undamped circuit model which show that the position of the resonance frequencies is only minimally influenced, even for high damping, i.e., low quality factors [14]. This can be understood by following the reasoning of [27]. In case of viscous damping, one has to distinguish between the

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

• − ri ), where ri0 is the initial position of the block and ν is the velocity vector of the slider, e.g., ν = (ν,0) when sliding is along the x axis. Therefore, the total driving force acting on the block i is Fmot(i) = Fs(i) + Σj Fint(ij). A damping force is added to avoid artificial block

• oscillations, where γ is the damping coefficient and is the velocity vector of the block. The damping coefficient γ is an arbitrary parameter. The results are independent of its value provided it is fixed in the underdamped regime: [34]. A pressure p is applied on the whole system, so that on each block

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

• that with the increase in IrMn layer thickness a nearly linear enhancement of the effective magnetic damping constant occurs, which is associated with the simultaneous influence of spin pumping and interlayer exchange coupling effects. An extrinsic contribution to the linewidth originating from the two

• -magnon scattering is also discussed. The AF-induced interfacial damping parameter is derived by studying the evolution of damping with inverse CoFeB thickness. The static magnetic measurements also reveal the interlayer exchange coupling across the IrMn layer both at room temperature and low temperature

• . Keywords: ferromagnetic resonance; interlayer exchange coupling; magnetic damping; magnetic thin films; spin pumping; Introduction Traditionally, antiferromagnets (AF) are known to play only a static role by pinning adjacent ferromagnetic (FM) layers via exchange bias in spin-valve devices [1]. Recently

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

• devices in which wear is a critical issue. At separations of several nanometers one talks about the phenomenon of non-contact friction. At first sight, this type of dissipation appears rather academic. However, the fundamental damping mechanisms of friction, which relate the energy released after

• voltage and/or the distance [188][189][190][191][192]. An example of particular interest is that of charge-density waves (CDW) where a superstructure is formed by a charge redistribution. Langer et al. have observed that the damping coefficient can be drastically changed on NbSe2, when the probing tip is

Tailoring polarization and magnetization of absorbing terahertz metamaterials using a cut-wire sandwich structure

• Hadi Teguh Yudistira,
• Shuo Liu,
• Tie Jun Cui and
• Han Zhang

Beilstein J. Nanotechnol. 2018, 9, 1437–1447, doi:10.3762/bjnano.9.136

• × 1015 s−1. ω, ωp,Au and ΓAu are the angular frequency, angular plasma frequency of gold, and damping constant of gold, respectively. Figure 3 presents the reflectance–transmittance–absorbance (RTA) simulation result of cut-wire (Figure 3a), cross-shaped (Figure 3b) and star-shaped sandwich structures

Electrostatically actuated encased cantilevers

• Benoit X. E. Desbiolles,
• Gabriela Furlan,
• Adam M. Schwartzberg,
• Paul D. Ashby and
• Dominik Ziegler

Beilstein J. Nanotechnol. 2018, 9, 1381–1389, doi:10.3762/bjnano.9.130

• Background: Encased cantilevers are novel force sensors that overcome major limitations of liquid scanning probe microscopy. By trapping air inside an encasement around the cantilever, they provide low damping and maintain high resonance frequencies for exquisitely low tip–sample interaction forces even when

• peaks include adding damping elements [5][6] or using alternative excitation methods such as resistive thermal [7][8], piezoelectric [9], electrostriction [10], or quartz-crystal tuning forks [11][12] that all solely excite the cantilever without inducing motion of the entire chip or the surrounding

• path remains very challenging. If the excitation electrode is approached too closely to the resonator, squeeze film damping or snap-in of the cantilever become another concern [24]. In our implementation with encased cantilevers these issues are solved by integrating the excitation electrode into the

Atomic-level characterization and cilostazol affinity of poly(lactic acid) nanoparticles conjugated with differentially charged hydrophilic molecules

• María Francisca Matus,
• Martín Ludueña,
• Cristian Vilos,
• Iván Palomo and
• Marcelo M. Mariscal

Beilstein J. Nanotechnol. 2018, 9, 1328–1338, doi:10.3762/bjnano.9.126

• the temperature with a damping of 100 timesteps. To corroborate the correct assembling methodology, several MD simulations of 100 ps were performed for 20, 40 and 80 PLA chains (Figure 1C). Data collected along the trajectories were used to calculate molecular properties such as a radius of gyration

Field-controlled ultrafast magnetization dynamics in two-dimensional nanoscale ferromagnetic antidot arrays

• Anulekha De,
• Sucheta Mondal,
• Sourav Sahoo,
• Saswati Barman,
• Yoshichika Otani,
• Rajib Kumar Mitra and
• Anjan Barman

Beilstein J. Nanotechnol. 2018, 9, 1123–1134, doi:10.3762/bjnano.9.104

• Kittel formula, The exchange stiffness constant A is obtained from literature [39]. A pulsed field of peak value of 30 Oe, 10 ps rise/fall time and 20 ps pulse duration is used perpendicular to the sample plane, while a damping coefficient α = 0.008 is used during dynamic simulations. The experimentally

Scanning speed phenomenon in contact-resonance atomic force microscopy

• Christopher C. Glover,
• Jason P. Killgore and
• Ryan C. Tung

Beilstein J. Nanotechnol. 2018, 9, 945–952, doi:10.3762/bjnano.9.87

• stiffness is now a series combination of the fluid film stiffness kf and the material stiffness ks. There may also be additional damping effects introduced by the fluid film, which we would like to address in future research studies. For instance, it is known that the modulation of the tip–sample contact

• has an effect on the friction [18][19]. Furthermore, this effect depends on the scan speed and can bring the system from a stick–slip state to a “steady sliding” state above a critical velocity [18]. It is noted that “a small viscous damping contribution in the tip–sample contact is sufficient enough

• to suppress stick–slip oscillations” [18]. It may be possible that the thin film acts as a source of viscous damping that allows the system to achieve a “steady sliding” state, above a critical velocity, which may have an effect on the CR measurements. The hydrodynamic lift force F varies

Combined pulsed laser deposition and non-contact atomic force microscopy system for studies of insulator metal oxide thin films

• Daiki Katsube,
• Hayato Yamashita,
• Satoshi Abo and
• Masayuki Abe

Beilstein J. Nanotechnol. 2018, 9, 686–692, doi:10.3762/bjnano.9.63

• same as in our previous studies [29][37][41][44][45][46][47][48]. To perform stable atomic resolution imaging in this chamber, a mechanism to fix the unit by double spring vibration isolation and eddy current damping [49] is provided, to prevent vibration noise. Therefore, it is possible to obtain

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

Beyond Moore’s technologies: operation principles of a superconductor alternative

• Igor I. Soloviev,
• Nikolay V. Klenov,
• Sergey V. Bakurskiy,
• Mikhail Yu. Kupriyanov,
• Alexander L. Gudkov and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2017, 8, 2689–2710, doi:10.3762/bjnano.8.269

• quite analogous to the one for a mechanical pendulum with the moment of inertia (capacitance here is analogous to mass), the viscosity factor 1/ωc (resistance determines damping), and the applied torque I/Ic. This simple analogy allows to consider a superconducting digital circuit as a net of coupled

Patterning of supported gold monolayers via chemical lift-off lithography

• Liane S. Slaughter,
• Kevin M. Cheung,
• Sami Kaappa,
• Huan H. Cao,
• Qing Yang,
• Thomas D. Young,
• Andrew C. Serino,
• Sami Malola,
• Jana M. Olson,
• Stephan Link,
• Hannu Häkkinen,
• Anne M. Andrews and
• Paul S. Weiss

Beilstein J. Nanotechnol. 2017, 8, 2648–2661, doi:10.3762/bjnano.8.265

• energy of the system damping to the energy added due to pulling. Core-level shifts were calculated for the Au atoms in the modeled structures that were removed from surfaces in the simulations. The density functional theory with the PBE functional was used again via GPAW to calculate the energies of the

Laser-assisted fabrication of gold nanoparticle-composed structures embedded in borosilicate glass

• Nikolay Nedyalkov,
• Mihaela Koleva,
• Nadya Stankova,
• Rosen Nikov,
• Mitsuhiro Terakawa,
• Yasutaka Nakajima,
• Lyubomir Aleksandrov and
• Reni Iordanova

Beilstein J. Nanotechnol. 2017, 8, 2454–2463, doi:10.3762/bjnano.8.244

• influence of the particle size can be taken into account by a damping parameter modification [33] included in the expression of the dielectric function. Here γ is the damping parameter, and νF is the Fermi velocity. The values for γ0, and A are taken from [33]. The dielectric function and the corresponding

Material property analytical relations for the case of an AFM probe tapping a viscoelastic surface containing multiple characteristic times

• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 2230–2244, doi:10.3762/bjnano.8.223

• negligible, but errors are expected in high-damping environments. Finally, we have not explored in detail the success of the analytical equations in terms of dynamic parameters (such as free amplitude and amplitude setpoint) but we have found in this exploratory study that typical tapping amplitudes (ca. 100

Velocity dependence of sliding friction on a crystalline surface

• Christian Apostoli,
• Giovanni Giusti,
• Jacopo Ciccoianni,
• Gabriele Riva,
• Rosario Capozza,
• Rosalie Laure Woulaché,
• Andrea Vanossi,
• Emanuele Panizon and
• Nicola Manini

Beilstein J. Nanotechnol. 2017, 8, 2186–2199, doi:10.3762/bjnano.8.218

• damping term acting on the physical degrees of freedom of the model. Moreover, such damping terms, beside affecting the dynamics, are characterized by a damping rate γ whose value is left to the arbitrary choice of the researcher. Finite-temperature is often simulated in the standard Langevin scheme

• , where to the viscous term one adds suitable Gaussian-distributed random forces, whose amplitude, via the fluctuation–dissipation theorem, is also affected by the value of γ [19]. A few approaches try to get rid of the arbitrariness of damping terms, describing dissipation explicitly. Microcanonical

• conservative simulations, for example, can describe the energy transfer into internal vibrational energy omitting all unphysical damping terms altogether [20][21][22][23][24][25]. The disadvantage of this approach is that, due to the finite and relatively small number of degrees of freedom available in a

High-stress study of bioinspired multifunctional PEDOT:PSS/nanoclay nanocomposites using AFM, SEM and numerical simulation

• Alfredo J. Diaz,
• Hanaul Noh,
• Tobias Meier and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 2069–2082, doi:10.3762/bjnano.8.207

• free cantilever resonance frequency, is directly related to stiffness (larger stiffness leads to larger frequency and vice-versa) [49], while the quality factor maps the sample damping of the cantilever tip oscillation (greater dissipation leads to lower quality factor and vice-versa) [50]. The contact

• thick samples (Figure 2a), it follows the trend of the frequency for PPSS and LAP, but not for MTM. For the measured area, the quality factor for MTM is lower than for the other samples, translating into more damping. The damping comes either from the confined viscoelastic material (the polymer) trapped

• discussed, for thinner films the properties of the thin films are expected to be dominated by the morphology of PEDOT:PSS. In the case of the nanocomposites, the damping mechanisms are also dominated by the polymer (since the clays are comparatively incompressible), and hence the quality factor is very

Adsorbate-driven cooling of carbene-based molecular junctions

• Giuseppe Foti and
• Héctor Vázquez

Beilstein J. Nanotechnol. 2017, 8, 2060–2068, doi:10.3762/bjnano.8.206

• junctions anchored to Au(100) electrodes [28]. We reported a strong dependence of transport properties on the atomistic structure of the metal/molecule interface and analyzed its implications on the current-induced damping and excitation of localized molecular vibrations [29]. We considered the case of a

• population of vibrational mode λ (excluding anharmonic coupling between vibrational modes) is [36][37][38]: where the coupling of vibrations to tunneling electrons and to bulk phonons are both taken into account. The parameter describes the damping of molecular vibrations with bulk phonons in the left (L

• –vibration couplings and the left and right spectral densities: In our analysis the damping term Jλ in Equation 1 is introduced as an external parameter. We assume a constant damping of vibrational modes into bulk phonons of Jλ/2 = JL = JR = 5 × 1010 Hz. In the following we thus omit the label λ in the

Stick–slip boundary friction mode as a second-order phase transition with an inhomogeneous distribution of elastic stress in the contact area

• Iakov A. Lyashenko,
• Vadym N. Borysiuk and
• Valentin L. Popov

Beilstein J. Nanotechnol. 2017, 8, 1889–1896, doi:10.3762/bjnano.8.189

• to the data from Figure 2a and Figure 4a. As it can be seen from Figure 5, Fx(X) is periodical (with damping oscillations in the second case, as the amplitude of the friction force decreases in time due to the heating of the lubricant). The presented dependencies have a regular form in contrast to

Scaling law to determine peak forces in tapping-mode AFM experiments on finite elastic soft matter systems

• Horacio V. Guzman

Beilstein J. Nanotechnol. 2017, 8, 968–974, doi:10.3762/bjnano.8.98

• approximations have not been designed to describe the forces for finite soft-matter systems in highly damping environments. In this article we use the term soft matter to describe polymeric surfaces and/or biological systems (isolated or packed arrays of proteins) with Young moduli in the range of 30–300 MPa [11

• these theoretical approximations have been applied to derive a parametrical equation for determining the peak force based on the addition of repulsive Hertzian and attractive van der Waals interactions in low-damping environments [21]. Here we have conceived a multivariate regression analysis to obtain

Near-field surface plasmon field enhancement induced by rippled surfaces

• Mario D’Acunto,
• Francesco Fuso,
• Ruggero Micheletto,
• Makoto Naruse,
• Francesco Tantussi and
• Maria Allegrini

Beilstein J. Nanotechnol. 2017, 8, 956–967, doi:10.3762/bjnano.8.97

• localized with localization centers on the nanogaps. It is well known that as a surface plasmon approaches a narrow gap, its group velocity decreases and its electric field increases. Let us treat the plasmons as damped harmonic oscillators linearly coupled and with damping rate γ(t) and ω(t) as the

• changes its parameters in space [53], while the QNM frequency is supposed to change monotonically with a decay rate . If both ξ and γ are constants, the time-dependent plasmon amplitude E(r,t) is now proportional to e(ξ−γ)t with a competition between the frequency decay rate ξ and the damping rate γ. If ξ