Coupled molecular and cantilever dynamics model for frequency-modulated atomic force microscopy

• Michael Klocke and
• Dietrich E. Wolf

Beilstein J. Nanotechnol. 2016, 7, 708–720, doi:10.3762/bjnano.7.63

• . It is shown how this may lead to a systematic shift between the periodic patterns obtained from the frequency and from the damping signal, respectively. Keywords: atomic force microscopy; frequency-modulated atomic force microscopy (FM-AFM); energy dissipation; Introduction The physical background

• ). Energy dissipation sets in abruptly as soon as the nominal distance drops below d < 1.2 and is basically constant for smaller distances. This is a typical sign for adhesion hysteresis: The sudden configurational change happens only if the tip comes close enough to the surface. Once it happened, the

• oppositely charged. The results, Figure 8, are clear indication of adhesion hysteresis: energy dissipation sets in abruptly as soon as the tip approaches the substrate closer than (nominally) 5.4 Å. At that point, also the reduced frequency shift γ = (Δf/fz)kzA3/2 changes abruptly. (The reduced frequency

Controlled graphene oxide assembly on silver nanocube monolayers for SERS detection: dependence on nanocube packing procedure

• Martina Banchelli,
• Bruno Tiribilli,
• Roberto Pini,
• Luigi Dei,
• Paolo Matteini and
• Gabriella Caminati

Beilstein J. Nanotechnol. 2016, 7, 9–21, doi:10.3762/bjnano.7.2

• energy dissipation of a SiO2-coated AT-cut 5 MHz quartz microcrystal were simultaneously measured at its resonant frequency and at the third, fifth, seventh, ninth and eleventh overtones. The temperature of the measuring cell was kept constant at 20 °C with a Peltier element connected to the TE module

Optimization of phase contrast in bimodal amplitude modulation AFM

• Mehrnoosh Damircheli,
• Amir F. Payam and
• Ricardo Garcia

Beilstein J. Nanotechnol. 2015, 6, 1072–1081, doi:10.3762/bjnano.6.108

• map compositional variations under the influence of conservative forces is a main advantage with respect to AFM phase imaging (tapping mode AFM), where the phase contrast is related to variations in energy dissipation [33]. In AM-AFM there are two interacting regimes, attractive and repulsive [2]. The

• function of the amplitude ratio, the amplitude values of the second mode and the kinetic energy ratios of the excited modes. We also study the phase contrast between different materials by including energy dissipation in the tip–sample interaction, by inverting the roles of the excited modes (indirect

• effect of energy dissipation in the bimodal phase contrast, in addition the above conservative force, we introduce the following non-conservative interaction [47]: The power dissipated in the sample for each mode is calculated by [47] Figure 3a,b show the dependence of versus A1/A01 when the tip–sample

Stick–slip behaviour on Au(111) with adsorption of copper and sulfate

• Nikolay Podgaynyy,
• Sabine Wezisla,
• Christoph Molls,
• Shahid Iqbal and
• Helmut Baltruschat

Beilstein J. Nanotechnol. 2015, 6, 820–830, doi:10.3762/bjnano.6.85

• of stick–slip behaviour at normal loads of less than 15 nN. In spite of non-stick–slip resolution the contact between tip and surface is preserved and energy dissipation is still observed. A transition to superlubricity would involve disappearing friction [35][36]. Since this is not the case here one

• investigated. Friction is minimal at the potential of zero charge, suggesting again the role of adsorbates for frictional energy dissipation. On the other hand, friction is particularly large when the adlayer is disordered at the potential of a phase transition, as shown here for the formation of the √3 × √3

Capillary and van der Waals interactions on CaF₂ crystals from amplitude modulation AFM force reconstruction profiles under ambient conditions

• Annalisa Calò,
• Oriol Vidal Robles,
• Sergio Santos and
• Albert Verdaguer

Beilstein J. Nanotechnol. 2015, 6, 809–819, doi:10.3762/bjnano.6.84

• contributions to the net energy dissipation by their physical origin and/or distance-dependence [34] has been the object of recent efforts in the direction of performing quantitative measurements with the AFM [35][36]. For example, Gadelrab and coauthors showed that the difference in the phase signal compared

• follows that if there is no energy dissipation, ΔΦ = 0. Numerical integration method The standard (single mode) equation of motion [27][51] of the cantilever has been implemented in the programming language C and solved with the use of a standard Euler algorithm, where ω is the angular drive frequency

• position. The reconstruction of the conservative force and the determination of the energy dissipation have been carried out by implementing the expressions in Equation 2 and Equation 4 in Matlab [53]. The raw amplitude and phase data have been processed both when dealing with the experimental data and

Entropy effects in the collective dynamic behavior of alkyl monolayers tethered to Si(111)

• Christian Godet

Beilstein J. Nanotechnol. 2015, 6, 583–594, doi:10.3762/bjnano.6.60

• chain segments located away from the head towards the molecular tail. The strain-induced formation of gauche defects, initiating at outer bonds (end-gauche) and proceeding inward (kinks and gauche–gauche conformers) [3][17][22] results into a disorder gradient. Another important issue related to energy

• dissipation mechanisms is the behavior of tethered OML under compressive and shear forces, as found in nano-tribology experiments, where external forces can cause conformational changes. Again, a disorder gradient results from the formation of gauche defects which can be reverted when the atomic force

A scanning probe microscope for magnetoresistive cantilevers utilizing a nested scanner design for large-area scans

• Tobias Meier,
• Alexander Förste,
• Ali Tavassolizadeh,
• Karsten Rott,
• Dirk Meyners,
• Roland Gröger,
• Günter Reiss,
• Eckhard Quandt,
• Thomas Schimmel and
• Hendrik Hölscher

Beilstein J. Nanotechnol. 2015, 6, 451–461, doi:10.3762/bjnano.6.46

• , atomic step edges of 2.54 Å height are resolved. For dynamic-mode experiments, the phase-shift signal is of high interest as it provides information about energy dissipation between tip and sample [60][61] and visualizes chemical contrasts [62]. To demonstrate this kind of measurement also with our TMR

• topography contrast in ambient conditions is most likely caused by the thin water films present on hydrophilic SiOx under ambient conditions [65]. This effect obscures the height difference between the FDTS and SiOx. However, as shown in Figure 7a, the difference of the energy dissipation between the two

• sample system, dissipative tip–sample forces are dominant. Therefore, a high phase-signal contrast can be observed and reveals the different materials of the sample due to different energy dissipation between tip and sample while the amplitude-signal feedback reveals no topographic features. b) On such

Dynamic force microscopy simulator (dForce): A tool for planning and understanding tapping and bimodal AFM experiments

• Horacio V. Guzman,
• Pablo D. Garcia and
• Ricardo Garcia

Beilstein J. Nanotechnol. 2015, 6, 369–379, doi:10.3762/bjnano.6.36

• ]. They explained the origin of the phase contrast observed on heterogeneous samples by tapping mode AFM in air [3] and liquid [4][5]. In the process, simulations validated the theory of AFM phase imaging in air [6][7], its use to identify energy dissipation processes [7] or to measure the energy

High-frequency multimodal atomic force microscopy

• Adrian P. Nievergelt,
• Jonathan D. Adams,
• Pascal D. Odermatt and
• Georg E. Fantner

Beilstein J. Nanotechnol. 2014, 5, 2459–2467, doi:10.3762/bjnano.5.255

• resonance. Panels b and e show the resonance frequency shift of the first higher resonant mode, and panels c and f show the drive amplitude needed to keep the first higher resonant mode at constant amplitude, related to the energy dissipation in the tip–sample interaction. a) Schematic of the drive

Modeling viscoelasticity through spring–dashpot models in intermittent-contact atomic force microscopy

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

Beilstein J. Nanotechnol. 2014, 5, 2149–2163, doi:10.3762/bjnano.5.224

• quantitative information about the dissipative and conservative tip–sample interactions by converting them to energy-based quantities, namely the dissipated power (Pts) and virial (Vts) [9][11]. Although several authors have achieved quantification of energy dissipation processes [12][13][14][15], the further

• Figure 4. Results of energy dissipation when a numerically simulated tip trajectory in intermittent contact AFM interacts with a Nafion model. (a) shows force–distance curves for tips driven at different eigenfrequencies (color coded). The inset in (a) shows the behavior of the dissipation as the

• use were: ke = 20 N/m, k1 = 10 N/m, k2 = 5 N/m, and c1 = c2 = 1.0 × 10−5 N·s/m. Time normalization has been carried out in (c) with respect to the fundamental period for ease of comparison. Results of energy dissipation when a tip interacts with a Nafion model under a numerically simulated trajectory

Dissipation signals due to lateral tip oscillations in FM-AFM

• Michael Klocke and
• Dietrich E. Wolf

Beilstein J. Nanotechnol. 2014, 5, 2048–2057, doi:10.3762/bjnano.5.213

• force microscopy (AFM); frequency-modulated atomic force microscopy (FM-AFM); energy dissipation; Introduction The usage of scanning probe microscopes requires an understanding of the physical processes during the scan, otherwise images can be misinterpreted. Due to the importance of frequency

• -modulated atomic force microscopy (FM-AFM), the physical processes involved have been studied intensively in the past [1]. This includes the relation between tip–surface interaction and frequency-shift [2], as well as features such as the energy dissipation during the scan [3], which is an interesting side

• for the understanding and correction of certain distortions seen in the actual images. Here, we enhance these studies by taking lateral dynamics of the tip into account and study the effect on the topography as well as on the energy dissipation signal. It is necessary to distinguish between the terms

Controlling the optical and structural properties of ZnS–AgInS₂ nanocrystals by using a photo-induced process

• Takashi Yatsui,
• Fumihiro Morigaki and
• Tadashi Kawazoe

Beilstein J. Nanotechnol. 2014, 5, 1767–1773, doi:10.3762/bjnano.5.187

• -radiative energy dissipation, and resulted in the increase of the emission intensity of the band edge. Using the emission spectra to control the nanocrystal size For the investigation of ways to control the size of ZAIS nanocrystals, we synthesized ZAIS nanocrystals with 532 nm irradiation (λ2) during the

Probing viscoelastic surfaces with bimodal tapping-mode atomic force microscopy: Underlying physics and observables for a standard linear solid model

• Santiago D. Solares

Beilstein J. Nanotechnol. 2014, 5, 1649–1663, doi:10.3762/bjnano.5.176

• ] and Garcia et al. [31] proved mathematically that when tip–sample energy dissipation is absent, the phase shift remains unchanged even if the elastic properties of the sample are non-uniform across the surface. This enables the user to directly map variations in energy dissipation based on the phase

• to obtain images of the sample topography, energy dissipation and elasticity of polymer surfaces immersed in a liquid environment [16]. We have also reported experiments in which images of Vts and Pts were compared for different control schemes applied to the higher mode, including open loop

Probing the electronic transport on the reconstructed Au/Ge(001) surface

• Franciszek Krok,
• Mark R. Kaspers,
• Alexander M. Bernhart,
• Marek Nikiel,
• Benedykt R. Jany,
• Paulina Indyka,
• Mateusz Wojtaszek,
• Rolf Möller and
• Christian A. Bobisch

Beilstein J. Nanotechnol. 2014, 5, 1463–1471, doi:10.3762/bjnano.5.159

• financial support from the Deutsche Forschungsgemeinschaft under the program “SFB616: Energy Dissipation at Surfaces” and the Polish National Science Center, grant no. DEC-2012/07/B/ST5/00906. Part of the research was carried out with equipment purchased with financial support from the European Regional

A nanometric cushion for enhancing scratch and wear resistance of hard films

• Katya Gotlib-Vainshtein,
• Olga Girshevitz,
• Chaim N. Sukenik,
• David Barlam and
• Sidney R. Cohen

Beilstein J. Nanotechnol. 2014, 5, 1005–1015, doi:10.3762/bjnano.5.114

• or spallation due to compressive stress. Thus, a large mismatch between the lateral stresses on the two components will lead to wear and to energy dissipation. The FEA modeling confirms the observed behavior. The modeling points to a mechanistic interpretation: (1) The extensive deformation of the

• scratch protection due to their hardness [6]. There are literature reports of the effect of hard-on-soft coatings wherein the soft component is only marginally softer and more compliant than the stiffer and harder film [12]. The softer underlying substrate is proposed to promote sliding and energy

• dissipation during deformation of the hard film. In their classic model of friction, Bowden and Tabor [13] divide the friction into two terms, a plowing term and an adhesion term. The latter is associated with friction arising from the energy required to break the adhesive bonds, and the former from the

Resonance of graphene nanoribbons doped with nitrogen and boron: a molecular dynamics study

• Ye Wei,
• Haifei Zhan,
• Kang Xia,
• Wendong Zhang,
• Shengbo Sang and
• Yuantong Gu

Beilstein J. Nanotechnol. 2014, 5, 717–725, doi:10.3762/bjnano.5.84

• with the results presented in Figure 2a, a much slower energy dissipation is found for the GNR with 1.89% B-dopant (see Figure 2b). We note that, although the GNR with a higher density of B-dopant might have a higher Q, the resonance frequency appears to have a consistent trend to decrease when the B

• % B- and N-dopants, a very high Q of about 8300 is observed, while for the case with 0.88% dopants, an extremely low Q of about 1980 is detected. Figure 7a depicts the results obtained from the case with 0.38% dopants. A fast energy dissipation is observed, with the resonance frequency being estimated

• amplitude of the external energy for the case with 0.76% B-dopant decreases linearly from 0.10 to 0.08 eV after 1200 ps. A non-uniform linear decrease fashion of the external energy is also detected in the defective GNR with 2.40% B-dopant. Figure 9b shows a fast energy dissipation at the beginning of the

Correction to "Energy dissipation in multifrequency atomic force microscopy"

• Valentina Pukhova,
• Francesco Banfi and
• Gabriele Ferrini

Beilstein J. Nanotechnol. 2014, 5, 667–667, doi:10.3762/bjnano.5.78

• /bjnano.5.78 Keywords: band excitation; multifrequency atomic force microscopy (AFM); phase reference; wavelet transforms; In the section "Energy dissipation" of the above manuscript, there is a typesetting error in the mathematical expressions after Equation 5. The correct form must be: The energy

Energy dissipation in multifrequency atomic force microscopy

• Valentina Pukhova,
• Francesco Banfi and
• Gabriele Ferrini

Beilstein J. Nanotechnol. 2014, 5, 494–500, doi:10.3762/bjnano.5.57

• energy dissipation is a fundamental aspect of the tip–sample interaction, allowing to quantify compositional contrast variations at the nanoscale [2]. The applied forces and the energy delivered to the sample are relevant for the imaging and the manipulation of soft materials in a variety of environments

• each flexural eigenmode upon impact. In the present work we build on that results to study in greater details the tip–sample force interactions separately for each mode and in particular the energy dissipation. Since the dissipative interactions are important in characterizing the compositional

• and third modes are not contact modes. This is proved by their frequency scaling, which is similar to that of free flexural modes and differs considerably from that of a pinned cantilever. For a discussion on this point we refer the reader to [5]. Energy dissipation The energy balance of each decaying

Effect of contaminations and surface preparation on the work function of single layer MoS₂

• Oliver Ochedowski,
• Kolyo Marinov,
• Nils Scheuschner,
• Artur Poloczek,
• Benedict Kleine Bussmann,
• Janina Maultzsch and
• Marika Schleberger

Beilstein J. Nanotechnol. 2014, 5, 291–297, doi:10.3762/bjnano.5.32

• DFG in the framework of the Priority Program 1459 Graphene (O.O., N.S.), the SFB 616 Energy dissipation on surfaces (K.M., B.K.B.), and from the ERC under Grant No. 259286 (J.M.). We thank M. Freudenberg for graphics support.

Frequency, amplitude, and phase measurements in contact resonance atomic force microscopies

• Gheorghe Stan and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2014, 5, 278–288, doi:10.3762/bjnano.5.30

• using the tapping-mode (amplitude modulation) technique [13], within which variations in the phase contrast can be directly related to changes in energy dissipation [14][15]. Conservative and dissipative interactions are generally expressed in terms of the virial (Vts) and the dissipated power (Pts

Friction behavior of a microstructured polymer surface inspired by snake skin

• Martina J. Baum,
• Lars Heepe and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2014, 5, 83–97, doi:10.3762/bjnano.5.8

• with acoustic emissions, to an increase in abrasion and to stronger energy dissipation, to an increase in maintenance costs of industrial facilities due to (1) the higher need of lubricants, (2) the replacement costs of machine parts, and (3) the loss of productivity due to maintenance. However, the

Exploring the retention properties of CaF₂ nanoparticles as possible additives for dental care application with tapping-mode atomic force microscope in liquid

• Matthias Wasem,
• Joachim Köser,
• Sylvia Hess,
• Enrico Gnecco and
• Ernst Meyer

Beilstein J. Nanotechnol. 2014, 5, 36–43, doi:10.3762/bjnano.5.4

• and on tooth enamel in liquid. From the phase-lag of the forced cantilever oscillation the local energy dissipation at the detachment point of the nanoparticle was determined. This enabled us to compare different as-synthesized CaF2 nanoparticles that vary in shape, size and surface structure. CaF2

• closely related to energy dissipation maps [3][4]. While phase imaging in ambient with high quality cantilever Q-factors is well established [5], a comprehensive model of the energy dissipation process in liquid is still missing since the first studies of AM-AFM measurements in liquid [6][7]. Recent

• studies have related the phase contrast, when measuring in liquid in which low Q-factors are found, to two origins: the excitation of higher eigenmodes and the energy dissipation on the sample surface [8][9]. In this work we show that for surface associated manipulation of nanoparticles in liquid, the

Structural development and energy dissipation in simulated silicon apices

• Samuel Paul Jarvis,
• Lev Kantorovich and
• Philip Moriarty

Beilstein J. Nanotechnol. 2013, 4, 941–948, doi:10.3762/bjnano.4.106

• , let alone due to variations in tip apices. Energy dissipation in NC-AFM measurements has most effectively been explained by adhesion hysteresis due to deformations in the tip–sample junction originating from bistable defects [31][32][33] or by structural relaxations within the larger structure of the

• tip structure through the examination of the energy dissipation during the dimer manipulation. A similar method is implemented in this work to assess the evolving structure of a silicon tip. In the current instance the tips are rotated through angles up to 360° around the surface normal axis, either

• of the tip relative to the surface, in some cases, can dramatically affect the chances of a major structural rearrangement. Energy dissipation in small apex clusters Presented in Figure 2 are simulated F(z) curves taken with the H3 (a) and D1 (b) tips positioned above the up (green and black

Energy transfer in complexes of water-soluble quantum dots and chlorin e6 molecules in different environments

• Irina V. Martynenko,
• Anna O. Orlova,
• Vladimir G. Maslov,
• Alexander V. Baranov,
• Anatoly V. Fedorov and
• Mikhail Artemyev

Beilstein J. Nanotechnol. 2013, 4, 895–902, doi:10.3762/bjnano.4.101

• quantum dots and chlorin e6 molecules form stable complexes that exhibit Förster resonance energy transfer (FRET) from quantum dots to chlorin e6 regardless of complex formation conditions. Competitive channels of photoexcitation energy dissipation in the complexes, which hamper the FRET process, were

• –tetrapyrrole complexes, a formation of competitive channels of nonradiative photoexcitation energy dissipation different from FRET may take place for both donor and acceptor [4]. The origin of these energy transfer channels is not completely understood. Several physical mechanisms have been proposed, for

• solubilizer. Since the FRET efficiency reaches only 30% of its maximum value, we can assume that quenching of QD PL cannot be explained only by FRET, which is responsible only for 30% of the quenching. Therefore, a presence of competitive channels of a nonradiative photoexcitation energy dissipation in QDs

Dynamic nanoindentation by instrumented nanoindentation and force microscopy: a comparative review

• Sidney R. Cohen and
• Estelle Kalfon-Cohen

Beilstein J. Nanotechnol. 2013, 4, 815–833, doi:10.3762/bjnano.4.93

• . Dynamic imaging modes that are commonly used in AFM provide the phase information, typically as an image channel measured and displayed simultaneously with the topographic image. The phase shift is interpreted as giving an estimate, generally qualitative, of the energy dissipation [92][93]. Nonetheless

• [82][94]. One caveat arising from the modulation techniques is that the phase lag signal carries information on additional dissipative processes other than viscoelastic energy dissipation, such as surface adhesion and capillary forces [95]. “On-the-fly” measurements of dissipation, which integrate the

• ]. Burnham et al., in an analysis of the mechanics of dynamic AFM contact, described the various modes, in which the AFM can be used to study energy dissipation [63]. They split the possible operation modes into three categories: force modulation, sample modulation and tip modulation. They found that a