Enhanced feedback performance in off-resonance AFM modes through pulse train sampling

• Mustafa Kangül,
• Navid Asmari,
• Santiago H. Andany,
• Marcos Penedo and
• Georg E. Fantner

Beilstein J. Nanotechnol. 2024, 15, 134–143, doi:10.3762/bjnano.15.13

• -order hold block. Thus, the control process can be represented with a sampler, an integrator, a delay element, and a zero-order hold block (Figure 1E-v.). To analyze the reference tracking quality of the controller, we model a unity gain closed-loop system (further information in Supporting Information

A review of demodulation techniques for multifrequency atomic force microscopy

• David M. Harcombe,
• Michael G. Ruppert and
• Andrew J. Fleming

Beilstein J. Nanotechnol. 2020, 11, 76–91, doi:10.3762/bjnano.11.8

• , consider the functional block diagram in Figure 7, where the integrator of the Lyapunov filter is replaced by the transfer function F(s). In this form, the direct-design demodulator follows a modulated–demodulated control loop [57] with a unity plant. This method differs from the Lyapunov filter as it does

Gas-sensing behaviour of ZnO/diamond nanostructures

• Marina Davydova,
• Alexandr Laposa,
• Jiri Smarhak,
• Alexander Kromka,
• Neda Neykova,
• Josef Nahlik,
• Jiri Kroutil,
• Jan Drahokoupil and
• Jan Voves

Beilstein J. Nanotechnol. 2018, 9, 22–29, doi:10.3762/bjnano.9.4

• remarkable semiconducting properties [20][21]. For instance, hydrogen-terminated NCD films exhibit changes in their surface conductivity in the presence of phosgene and could be utilized as an integrator-type gas sensor [22][23]. Up to now, many research groups have focused on nitrogen dioxide (NO2) sensing

A review of demodulation techniques for amplitude-modulation atomic force microscopy

• Michael G. Ruppert,
• David M. Harcombe,
• Michael R. P. Ragazzon,
• S. O. Reza Moheimani and
• Andrew J. Fleming

Beilstein J. Nanotechnol. 2017, 8, 1407–1426, doi:10.3762/bjnano.8.142

• such, this method can be improved by employing a high-pass filter on the input and post-integration filters [43], either in the form of a direct notch filter at the second harmonic or by passing the output through another numerical integrator [41]. Intuitively, as Figure 10 illustrates, this method can

• frequency flp. With a known measurement noise covariance R, the Kalman filter is tuned based on the assumed covariance Q and the Lyapunov filter can be tuned by setting the integrator gain γ. The moving average filter

Multimodal cantilevers with novel piezoelectric layer topology for sensitivity enhancement

• Steven Ian Moore,
• Michael G. Ruppert and
• Yuen Kuan Yong

Beilstein J. Nanotechnol. 2017, 8, 358–371, doi:10.3762/bjnano.8.38

• which determine cut-off frequency and gain are chosen as Cs = 100 pF, Rs = 10 MΩ and Rp = 1 MΩ. To prevent oscillations in the instrumentation circuit, an integrator is used to control the charge on Cs. The integrator’s high gain at low frequencies allows the charge to be accurately controlled and their

Length-extension resonator as a force sensor for high-resolution frequency-modulation atomic force microscopy in air

• Hannes Beyer,
• Tino Wagner and
• Andreas Stemmer

Beilstein J. Nanotechnol. 2016, 7, 432–438, doi:10.3762/bjnano.7.38

• . The excitation signal is used as input signal of a slow proportional-integral-controller. The setpoint of this slow feedback is determined by the excitation measured at the desired Δf topography setpoint, and thus the desired tip–sample distance. We mainly apply low integrator gain only, resulting in

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

• operations such as data storing and visualization. For the simulations, it is important to choose appropriate values for the numerical integrator, in particular the number of periods, interval of periods (to calculate the steady state), and the average tip–surface distance step to guarantee that the

Gas sensing properties of nanocrystalline diamond at room temperature

• Marina Davydova,
• Pavel Kulha,
• Alexandr Laposa,
• Karel Hruska,
• Pavel Demo and
• Alexander Kromka

Beilstein J. Nanotechnol. 2014, 5, 2339–2345, doi:10.3762/bjnano.5.243

• , the three-dimensional model of the current density distribution of the hydrogenated NCD describes the transient flow of electrons between interdigitated electrodes and the hydrogenated NCD surface, that is, the formation of a closed current loop. Keywords: gas sensor; integrator; interdigitated

• results demonstrated that the hydrogenated diamond sensor exhibited a clear response to each sequence of NH3, and this behavior indicated that the H-terminated NCD sensor demonstrated an integrator-type gas response. Figure 2a shows an SEM image of the surface morphology of the sensor substrate (Si/SiO2

• evidence of the integrator property was observed. Overall, the hydrogenated diamond sensors exhibited a response to each sequence of NH3. These behaviors indicated that the H-terminated NCD sensors were able to accumulate NH3 gas in its water adsorbate layer, which confirms the integrator-type gas sensor

Interpreting motion and force for narrow-band intermodulation atomic force microscopy

• Daniel Platz,
• Daniel Forchheimer,
• Erik A. Tholén and
• David B. Haviland

Beilstein J. Nanotechnol. 2013, 4, 45–56, doi:10.3762/bjnano.4.5

• use the adaptive step-size integrator CVODE [37] with root detection to properly treat the piecewise definition of the tip–surface force in Equation 40. From the simulated tip motion we determine the motion and the force envelope functions and and reconstruct FI(A) and FQ(A) according to Equation 37

Simultaneous current, force and dissipation measurements on the Si(111) 7×7 surface with an optimized qPlus AFM/STM technique

• Zsolt Majzik,
• Martin Setvín,
• Andreas Bettac,
• Albrecht Feltz,
• Vladimír Cháb and
• Pavel Jelínek

Beilstein J. Nanotechnol. 2012, 3, 249–259, doi:10.3762/bjnano.3.28

• ) the amplifier gain drops −20 dB/decade, being proportional to 1/f. In this regime, the amplifier behaves as an integrator circuit and the value of Cp becomes dominant. The voltage at the capacitor is equal to the charge q on the capacitor divided by its capacitance, therefore Vout = q/Cp. Because the