Background Accurate mechanical characterization by the atomic force microscope at highest spatial resolution requires that topography is deconvoluted from indentation. The measured height of nanoscale features in (AFM) almost always smaller than true value, which often explained away as sample deformation, formation salt deposits and/or dehydration. We show real nano-objects cannot be obtained directly: a result arising consequence local probe-sample geometry. Methods and Findings have...

Standard models accounting for capillary interactions typically involve expressions that display a significant decay in force with separation. These forces are commonly investigated the nanoscale atomic microscope. Here we show experimental observations not predicted by these common dynamic interactions. Since microscopy methods cantilever is vibrated over surface, nanoscopic tip submitted to nonlinear sample periodic fashion. That is, dependencies involved can be probed. We describe two...

The dynamics of the oscillating microcantilever for amplitude modulation atomic force microscopy (AM AFM) operating in air is well understood theoretically but experimental outcomes are still emerging. We use double-stranded DNA on mica as a model biomolecular system investigating connection between theory and experiment. A demonstration that switching two cantilever oscillation states stochastic nature achieved, it can be induced by means topographical anomalies surface. Whether one or...

A way to operate fundamental mode amplitude modulation atomic force microscopy is introduced which optimizes stability and resolution for a given tip size shows negligible wear over extended time periods (∼24 h). In small set-point (SASS) imaging, the cantilever oscillates with sub-nanometer amplitudes in proximity of sample, without requirement using large drive forces, as dynamics smoothly lead surface through water layer. SASS demonstrated on single molecules double-stranded DNA ambient...

We describe fundamental energy dissipation in dynamic nanoscale processes terms of the localization interactions. In this respect, areal density dissipated per cycle and effective area interaction which each process occurs are calculated for four elementary dissipative processes. It is ratio between these two, we term M, that provides information about how localized interactions are. While our results general, use concepts from atomic force microscopy to physical phenomenon. show neither...

In ambient conditions, nanometric water layers form on hydrophilic surfaces covering them and significantly changing their properties characteristics. Here we report the excitation of subharmonics in amplitude modulation atomic force microscopy induced by intermittent contacts. Our simulations show that there are several regimes operation depending whether is perturbation layers. Single period orbitals, where never induced, follow only when tip either permanent contact with or pure...

Since the inception of atomic force microscope (AFM), dynamic methods (dynamic microscopy) have been very fruitful by establishing to quantify dissipative and conservative forces in nanoscale providing a means apply gentle samples with high resolution. Here, we discuss developments that cover over decade our work on energy dissipation, phase contrast, extraction relevant material properties from observables. We describe attempts recover via one-dimensional amplitude curves models explore...

The multifrequency formalism is generalized and exploited to quantify attractive forces, i.e., van der Waals interactions, with small amplitudes or gentle forces in bimodal trimodal atomic force microscopy (AFM). spectroscopy higher modes, including AFM, can outperform AFM for material property quantification. Bimodal the second mode valid when drive amplitude of first approximately an order magnitude larger than that mode. error increases but decreases third a decreasing ratio. Externally...

Transitions between the attractive and repulsive force regimes for amplitude modulation atomic microscopy (AFM) can be either discontinuous, with a corresponding jump in phase, or continuous smooth. During transitions, peak average forces up to an order of magnitude higher when these are discrete. Under certain circumstances, example, tip radius is relatively large (e.g. R > 20–30 nm) high cantilever free amplitudes A 0 40–50 nm), L state reached low set-points only sp / < 0.30). We...

In dynamic atomic force microscopy, nanoscale properties are encoded in the higher harmonics. Nevertheless, when gentle interactions and minimal invasiveness required, these harmonics typically undetectable. Here, we propose to externally drive an arbitrary number of exact above noise level. this way, multiple contrast channels that sensitive compositional variations made accessible. Numerical integration equation motion shows external introduction harmonic frequencies does not compromise...

Periodicity is fundamental for quantification and the application of conservation principles many important systems. Here, we discuss periodicity in context bimodal atomic force microscopy (AFM). The relationship between excited frequencies shown to affect control both experimental observables main expressions quantified via these observables, i.e., virial energy transfer expressions, which form basis AFM theory. presence a frequency further simplifies theory leads close solutions....

Multifrequency atomic force microscopy holds promise as a method to provide qualitative and quantitative information about samples with high spatial resolution. Here, we experimental evidence of the excitation subharmonics in ambient conditions regions where capillary interactions are predicted be mechanism excitation. We also experimentally decouple second for subharmonic that is highly independent environmental such relative humidity. This implies material properties could mapped....

Here we present the Mendeleev-Meyer Force Project which aims at tabulating all materials and substances in a fashion similar to periodic table. The goal is group tabulate using nanoscale force footprints rather than atomic number or electronic configuration as process divided into: (1) acquiring data from materials, (2) parameterizing raw into standardized input features generate library, (3) feeding library an algorithm generate, enhance exploit model identify material property. We propose...

Quantification of conservative forces in multifrequency atomic force microscopy requires solving the general equations theory expressed terms virials interaction. Power law expressions are commonly utilized when dealing with electrostatic, ferroelectric, magnetic, or long range (van der Waals) forces. Here, we discuss modeled power laws (n), where exponent n covers = 2–5, and employ to explore relevant parameter space. Numerical integration motion suggest that only a narrow operational...

Multifrequency atomic force microscopy holds promise as a tool for chemical and topological imaging with nanoscale resolution. Here, we solve the equation of motion exactly fundamental mode in terms cantilever mean deflection, frequency oscillation, higher harmonic amplitudes phases. The provides information about force, dissipation, variations magnitude attractive repulsive components during an oscillation cycle. contributions harmonics to position, velocity, acceleration can be added...

Amplitude modulation atomic force microscopy allows quantifying energy dissipation in the nanoscale with great accuracy use of analytical expressions that account for fundamental frequency and higher harmonics. Here, we focus on effects sub-harmonic excitation its quantification. While there might be several mechanisms inducing sub-harmonics, a general expression to quantify whenever sub-harmonics are excited is provided. The generalization previous findings. We validate via numerical...

In dynamic atomic force microscopy (AFM) the cantilever is vibrated and its dynamics are monitored to probe sample with nanoscale resolution. Amplitude frequency modulation (AM-AFM FM-AFM) have established themselves as most powerful methods in field. Nevertheless, it still debatable whether one or other technique preferred a given medium experiment. Here, we quantitatively establish compare limitations resolution of both techniques by introducing concept spatial horizon (SH) quantifying it....

A formalism to extract and quantify unknown quantities such as sample deformation, the viscosity of surface energy hysteresis in amplitude modulation atomic force microscopy is presented. Recovering unknowns only requires cantilever be accurately calibrated dissipative processes occurring during deformation well modeled. The theory validated by comparison with numerical simulations shown able provide, principle, values picometer resolution.

An averaged large-signal modelling method for resonant converters is presented, which based on the classification of state variables according to their dynamic behaviour. The technique applied a series-parallel converter, controlled switching at zero-resonant current. Based model, sliding mode controller this converter proposed, provides robustness in relation external disturbances and good response output voltage.

Establishing the presence or absence of nanoscale compositional heterogeneity with resolution is becoming instrumental for development many fields science. Force versus distance measurements and parameters directly indirectly derived from these profiles can be potentially employed this purpose sophisticated instruments such as atomic force microscope (AFM). On other hand, standards are necessary to reproducibly conclusively support hypothesis experimental data still emerging. Here, we define...

A Stewart platform is a kind of parallel robot which can be used for wide variety technological and industrial applications. In this paper, designed assembled at the Universitat Politecnica de Catalunya (UPC) by our research group presented. The main objective to overcome enormous difficulties that arise when real-time vision-based control fast moving object placed on these mechanisms required. addition, description its geometric characteristics, calibration process, together with an...

Multifrequency atomic force microscopy (AFM) enhances resolving power, provides extra contrast channels, and is equipped with a formalism to quantify material properties pixel by pixel. On the other hand, multifrequency AFM lacks ability extract examine profile validate given model while scanning. We propose exploiting data-driven algorithms, i.e., machine learning packages, predict optimum from observables of This approach allows distinguishing between different phenomena selecting suitable...

When we speak of nanometric water films on surfaces are speaking about a truly ubiquitous phenomenon in nature. All exposed to ambient conditions covered by thin film that affects or mediates surface chemistry, general physical-chemical processes surfaces, and even solid–solid interactions. We have investigated this for over decade exploiting dynamic atomic force microscopy (1) described how these layers affect apparent height measurements, (2) analyzed the excitation subharmonics, (3) its...

The vibrations that a shaft suffers when rotating affect both the friction and subsequent wear of shaft. main objective this paper is to present an academic experimental prototype allows controlling through magnetic levitation. control was carried out with microcontroller, electromagnets, proximity sensors. Other sensors regulators were also added model allow parameterization obtaining data for analysis. According experiments performed in laboratory, proposed digital controller capable...