A simple and efficient quasi 3-dimensional viscoelastic model and software for simulation of tapping-mode atomic force microscopy

• Santiago D. Solares

Beilstein J. Nanotechnol. 2015, 6, 2233–2241, doi:10.3762/bjnano.6.229

• that a useful avenue of research may be the study of tip–sample force ‘signatures’ for different viscoelastic models, as proposed through simulations in [17], where the tip–sample interaction force curve is acquired using spectral inversion methods [18][19] and the force is plotted not only in terms of

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

• capture both stress relaxation and creep compliance, which are basic time-dependent properties exhibited by viscoelastic surfaces. It is comprised by a Linear Maxwell arm arranged in parallel with a spring (Figure 3a) and has been recently used in the context of multifrequency and spectral inversion AFM

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

• with constant amplitudes for both eigenmodes. There also exist methods for the real-time acquisition of force curves, from which conservative and dissipative interactions can be studied. Specifically, the spectral inversion method, originally introduced by Stark et al. [25] and later improved by Sahin

• possible even with conventional force–distance curves (force vs distance), although it assumes very high accuracy in the acquisition of the tip–sample force curve through the spectral inversion method [26]. In practice there exist limitations that preclude such accuracy [38]. The development of new real

Multi-frequency tapping-mode atomic force microscopy beyond three eigenmodes in ambient air

• Santiago D. Solares,
• Sangmin An and
• Christian J. Long

Beilstein J. Nanotechnol. 2014, 5, 1637–1648, doi:10.3762/bjnano.5.175

• driven simultaneously or sequentially at more than one frequency [1]. Often these frequencies correspond to different cantilever eigenmodes [2][3][4][5][6][7][8][9][10][11][12], but there are also methods involving single-eigenmode multi-frequency excitation [13][14][15] and spectral inversion methods in

Towards 4-dimensional atomic force spectroscopy using the spectral inversion method

• Jeffrey C. Williams and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2013, 4, 87–93, doi:10.3762/bjnano.4.10

• Jeffrey C. Williams Santiago D. Solares Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA 10.3762/bjnano.4.10 Abstract We introduce a novel and potentially powerful, yet relatively simple extension of the spectral inversion method, which offers the

• possibility of carrying out 4-dimensional (4D) atomic force spectroscopy. With the extended spectral inversion method it is theoretically possible to measure the tip–sample forces as a function of the three Cartesian coordinates in the scanning volume (x, y and z) and the vertical velocity of the tip, through

• a single 2-dimensional (2D) surface scan. Although signal-to-noise ratio limitations can currently prevent the accurate experimental implementation of the 4D method, and the extraction of rate-dependent material properties from the force maps is a formidable challenge, the spectral inversion method