Dual-heterodyne Kelvin probe force microscopy

• Benjamin Grévin,
• Fatima Husainy,
• Dmitry Aldakov and
• Cyril Aumaître

Beilstein J. Nanotechnol. 2023, 14, 1068–1084, doi:10.3762/bjnano.14.88

• time-periodic surface electrostatic potential generated under optical (or electrical) pumping with an atomic force microscope. The modulus and phase coefficients are probed by exploiting a double heterodyne frequency mixing effect between the mechanical oscillation of the cantilever, modulated

• achieved by using two numerical lock-in amplifiers configured in cascade. Dual-heterodyne KPFM (DHe-KPFM) can be used to map any harmonic (amplitude/phase) of the time-periodic surface potential at a standard scanning speed. The Fourier spectrum (series of harmonics) can also be recorded in spectroscopic

• reference substrate, a bulk organic photovoltaic heterojunction thin film, and an optoelectronic interface obtained by depositing caesium lead bromide perovskite nanosheets on a graphite surface. The conclusion provides perspectives for future improvements and applications. Keywords: heterodyne

High–low Kelvin probe force spectroscopy for measuring the interface state density

• Ryo Izumi,
• Masato Miyazaki,
• Yan Jun Li and
• Yasuhiro Sugawara

Beilstein J. Nanotechnol. 2023, 14, 175–189, doi:10.3762/bjnano.14.18

• apply an AC bias voltage at frequencies lower than the cutoff frequency fc of carrier transport, and heterodyne FM-KPFM, based on the heterodyne effect (frequency conversion effect) between mechanical oscillation of the cantilever and electrostatic force oscillation, is used to apply an AC bias voltage

• consider the case in which the frequency of the AC bias voltage is higher than the cutoff frequency fc of the carrier transport between the interface and bulk states. We assume that the heterodyne FM method [21] is used and that an AC bias voltage with a high frequency near twice the vibration frequency of

Comparing the performance of single and multifrequency Kelvin probe force microscopy techniques in air and water

• Jason I. Kilpatrick,
• Emrullah Kargin and
• Brian J. Rodriguez

Beilstein J. Nanotechnol. 2022, 13, 922–943, doi:10.3762/bjnano.13.82

• placed on an eigenmode in order to measure VCPD with enhanced SNR since In this paper we refer to the use of two electrical drives and their products as electrodyne-KPFM (ED-KPFM). In order to access higher spatial resolution, bandwidth, and SNR, heterodyne-KPFM (Het-KPFM) was developed [57] whereby the

• electrical drives are employed (ED). Mixing modes require √2 less VAC than DH-based modes. For heterodyne-KPFM both mechanical, ωm, and electrical, ωe, signals are applied. Under conditions where VDC = 0 we can obtain the amplitudes of the mixing harmonics (see Appendix II) proportional to AmC″, where Am is

• comparison we include AmC″ for both models as this is the equivalent term in the mechanically coupled KPFM modes. We observe that the capacitance gradient contribution of the end of the probe is greater for modes based on C′ (i.e., non-heterodyne modes) for both sphere- and apex-based models. This is helpful

Direct measurement of surface photovoltage by AC bias Kelvin probe force microscopy

• Masato Miyazaki,
• Yasuhiro Sugawara and
• Yan Jun Li

Beilstein J. Nanotechnol. 2022, 13, 712–720, doi:10.3762/bjnano.13.63

• . Indeed, there remains an issue that the modulation frequency has the constraint of a transfer function of cantilever dynamics and the bandwidth of the PLL. We believe that this issue will be solved by future work such as using a heterodyne detection scheme [65][66][67]. It is noted that AC-KPFM observes

• it would be useful to operate AC-KPFM with a heterodyne detection scheme [65][66][67] in order to reduce a photothermal effect on the cantilever dynamics [68][69] and measure the fast SPV phenomena. The AC-KPFM method is utilized not only for SPV measurements, but also for direct measurements of

A wideband cryogenic microwave low-noise amplifier

• Boris I. Ivanov,
• Dmitri I. Volkhin,
• Ilya L. Novikov,
• Dmitri K. Pitsun,
• Dmitri O. Moskalev,
• Ilya A. Rodionov,
• Evgeni Il’ichev and
• Aleksey G. Vostretsov

Beilstein J. Nanotechnol. 2020, 11, 1484–1491, doi:10.3762/bjnano.11.131

• stable microwave sweeping signal generator (marked as “μ-wave” generator in Figure 5) were used for spectroscopy measurements. The standard heterodyne measurement method was used. A superconducting Nb coil was used for tuning the qubit eigenfrequency for each experiment. The coil was biased by means of a

Stochastic excitation for high-resolution atomic force acoustic microscopy imaging: a system theory approach

• Edgar Cruz Valeriano,
• José Juan Gervacio Arciniega,
• Christian Iván Enriquez Flores,
• Susana Meraz Dávila,
• Joel Moreno Palmerin,
• Martín Adelaido Hernández Landaverde,
• Yuri Lizbeth Chipatecua Godoy,
• Aime Margarita Gutiérrez Peralta,
• Rafael Ramírez Bon and
• José Martín Yañez Limón

Beilstein J. Nanotechnol. 2020, 11, 703–716, doi:10.3762/bjnano.11.58

• resonance frequencies are often labeled as acoustic or ultrasonic methods due to the frequency range of the vibrations involved (from 100 kHz to 3 MHz) [1][9][12]. Among them are ultrasonic force microscopy (UFM) [13], heterodyne force microscopy [14], ultrasonic atomic force microscopy (UAFM), atomic force

Implementation of data-cube pump–probe KPFM on organic solar cells

• Benjamin Grévin,
• Olivier Bardagot and
• Renaud Demadrille

Beilstein J. Nanotechnol. 2020, 11, 323–337, doi:10.3762/bjnano.11.24

• method consists in increasing the detection bandwidth by using the so-called heterodyne mode [6][7][8][9] or dissipative electrostatic force modulation [10][11]. To probe the photocarrier lifetime in photovoltaic materials, another option consists in analyzing the dependence of the time-averaged KPFM

• , the S/N ratio becomes too low to perform stable pp-KPFM experiments at a useful bandwidth. To verify this hypothesis, further experiments and developments are needed. In particular, we plan to increase the S/N ratio by using a heterodyne scheme [6] instead of the standard frequency-modulation mode for

• of spectroscopic pp-KPFM, for instance by using a heterodyne or a side-band detector. Further insights will also be gained by comparing different kinds of photovoltaic materials, for which the illumination-dependence of the S/N ratio may be different. In particular, we plan to investigate silicon

Quantitative comparison of wideband low-latency phase-locked loop circuit designs for high-speed frequency modulation atomic force microscopy

• Kazuki Miyata and
• Takeshi Fukuma

Beilstein J. Nanotechnol. 2018, 9, 1844–1855, doi:10.3762/bjnano.9.176

• common methods of expanding the input frequency range is heterodyne conversion using a BPF (Figure 2b). In this method, an input signal with a frequency of ω is multiplied by sine and cosine waves with frequencies of (ωIF − ω), producing ωIF and (ωIF − 2ω) components (Figure 2b(i)). While the (ωIF − 2ω

Know your full potential: Quantitative Kelvin probe force microscopy on nanoscale electrical devices

• Amelie Axt,
• Ilka M. Hermes,
• Victor W. Bergmann,
• Niklas Tausendpfund and
• Stefan A. L. Weber

Beilstein J. Nanotechnol. 2018, 9, 1809–1819, doi:10.3762/bjnano.9.172

• mode; AM off resonance; AM second eigenmode; cross section; crosstalk; field effect transistor; FM-KPFM; frequency modulation heterodyne; frequency modulation sideband; quantitative Kelvin probe force microscopy; solar cells; Introduction In this study, we compare the most commonly used amplitude

• techniques under ambient conditions. We compare AM-KPFM in lift mode, on the second eigenmode and off resonance, as well as FM-KPFM with double sideband detection and heterodyne FM-KPFM. Theory KPFM [29] utilizes a conductive SFM tip as Kelvin probe [30] to map electrical surface potential variations on a

• . Nevertheless, choosing ωm too high shifts the sidebands further away from the resonance frequency, decreasing the SNR. Thus, FM sideband KPFM typically has to be performed at higher AC voltages and/or at low detection bandwidths, limiting the speed of the measurement. In FM Heterodyne KPFM [26][38], the

Optical near-field mapping of plasmonic nanostructures prepared by nanosphere lithography

• Gitanjali Kolhatkar,
• Alexandre Merlen,
• Jiawei Zhang,
• Chahinez Dab,
• Gregory Q. Wallace,
• François Lagugné-Labarthet and
• Andreas Ruediger

Beilstein J. Nanotechnol. 2018, 9, 1536–1543, doi:10.3762/bjnano.9.144

• homodyne [16], heterodyne [17] or pseudoheterodyne [18] interferometry. However, these methods are challenging to put in place and require complex analytical devices. In certain cases, the interpretation of the pictures is far from being straightforward. In this work, we introduce a simple method to image

• -in or heterodyne detection to enhance the near-field signal [35][36]. While these techniques were able to successfully perform optical imaging, the data analysis remains highly complex. Compared to these methods, our approach offers several advantages: It is a non-destructive technique that does not

Kelvin probe force microscopy for local characterisation of active nanoelectronic devices

• Tino Wagner,
• Hannes Beyer,
• Patrick Reissner,
• Philipp Mensch,
• Heike Riel,
• Bernd Gotsmann and
• Andreas Stemmer

Beilstein J. Nanotechnol. 2015, 6, 2193–2206, doi:10.3762/bjnano.6.225

• below the thermal noise limited bandwidth of the cantilever [24], but the modulation induced by rough surfaces as well as the desired scan bandwidth establish lower limits. Furthermore, the sideband transfer function explains the higher resolution obtained by heterodyne amplitude-modulated KFM [47]. In

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

• explored; these include heterodyne optical beam and interferometric detection [32][33][34] and current-based translinear readout circuitry [35]. Of these approaches, the latter shows excellent potential for low-noise and high-bandwidth direct OBD readout. Surmounting these technological challenges has thus

Single-pass Kelvin force microscopy and dC/dZ measurements in the intermittent contact: applications to polymer materials

• Sergei Magonov and
• John Alexander

Beilstein J. Nanotechnol. 2011, 2, 15–27, doi:10.3762/bjnano.2.2

• response, which is detected by the phase signal or Y component signal of the LIA-1, is seen at the heterodyne frequencies ωmech ± ωelec. When the KFM servo is on, the heterodyne sidebands practically disappear and the DC voltage equals the contact potential difference. This AM–FM procedure is similar to