Adiabatic superconducting cells for ultra-low-power artificial neural networks

• Andrey E. Schegolev,
• Nikolay V. Klenov,
• Igor I. Soloviev and
• Maxim V. Tereshonok

Beilstein J. Nanotechnol. 2016, 7, 1397–1403, doi:10.3762/bjnano.7.130

• as a neuron whose activation function usually has a sigmoid-like shape. We start our pursuit of the MLP artificial neuron with an analysis of a simple quantron (or single-junction superconducting interferometer, Figure 1a) transfer function. This function links the applied magnetic flux, ΦX, with

• connection of two s-cells in order to obtain a bell-shaped transfer function from two sigmoid functions. Note that the resulting scheme is quite analogous to the above mentioned QFP. The cell is a two-junction interferometer with a total normalized inductance l, composed of two Josephson junctions J1 and J2

• shunted by inductance lq. Once again, the excitation current IX is applied to a control line, which is magnetically coupled to the symmetrical arms of the interferometer. One can write the equations for a Gauss cell by analogy with Equation 1 and Equation 2 in terms of the sum and difference phases, θ

Understanding interferometry for micro-cantilever displacement detection

• Alexander von Schmidsfeld,
• Tobias Nörenberg,
• Matthias Temmen and
• Michael Reichling

Beilstein J. Nanotechnol. 2016, 7, 841–851, doi:10.3762/bjnano.7.76

• displacement noise spectral density strongly decreases with decreasing distance between the fiber-end and the cantilever, yielding a noise floor of 24 fm/Hz0.5 under optimum conditions. Keywords: displacement noise spectral density; interferometer; non-contact atomic force microscope (NC-AFM); opto-mechanic

• effects; Introduction A common method for measuring the displacement of a micro-cantilever or another micro-mechanical device is interferometric displacement detection. The most basic interferometer setup is the Michelson interferometer using two mirrors for the superposition of two light beams [1][2]. A

• related interferometric setup based on multi-beam interference in an optical cavity is the Fabry-Pérot interferometer typically used in form of an etalon in spectroscopy, lasers, and optical telecommunication [3] for precise wavelength selection within a certain free spectral range [4]. The Fabry–Pérot

Highly compact refractive index sensor based on stripe waveguides for lab-on-a-chip sensing applications

• Chamanei Perera,
• Kristy Vernon,
• Elliot Cheng,
• Juna Sathian,
• Esa Jaatinen and
• Timothy Davis

Beilstein J. Nanotechnol. 2016, 7, 751–757, doi:10.3762/bjnano.7.66

• outcome of this paper will prove beneficial in highly compact, label-free and highly sensitive refractive index analysis. Keywords: interferometer; sensing; surface plasmons; waveguides; Introduction Plasmons are coherent oscillations of free electrons existing on metal dielectric interfaces and are

• excitation. The plasmonic Mach–Zehnder interferometer (MZI) is one such alternative passive nano-optical device used in refractive index sensing applications [3][5][15][16]. In physics, a MZI is a device used to determine the relative phase shift variations between two collimated beams derived from splitting

• ]. MZIs can be designed to be wavelength specific and more compact using waveguide structures. Vernon et al. proposed a compact interferometer design using stripe waveguide coupling to measure the change in the refractive index of a sample using the change in the output intensity [19]. The stripe

Correlative infrared nanospectroscopic and nanomechanical imaging of block copolymer microdomains

• Benjamin Pollard and
• Markus B. Raschke

Beilstein J. Nanotechnol. 2016, 7, 605–612, doi:10.3762/bjnano.7.53

• suppressed by a lock-in detector (HF2, Zurich Instruments) demodulating at the third harmonic of the tip tapping frequency. Tip-scattered light is recombined at the detector with light of known phase from the reference arm in an asymmetric Michelson interferometer geometry, allowing for the determination of

Imaging of carbon nanomembranes with helium ion microscopy

• André Beyer,
• Henning Vieker,
• Robin Klett,
• Hanno Meyer zu Theenhausen,
• Polina Angelova and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2015, 6, 1712–1720, doi:10.3762/bjnano.6.175

• other suitable indicators that are detectable by optical microscopy. In addition, optical imaging with a Mirau interferometer allows the detection of the vibrational modes of bare CNMs with a resolution limited by the light wavelength [15]. The imaging of CNMs with higher magnification requires charged

Radiation losses in the microwave K_u band in magneto-electric nanocomposites

• Talwinder Kaur,
• Sachin Kumar,
• Jyoti Sharma and
• A. K. Srivastava

Beilstein J. Nanotechnol. 2015, 6, 1700–1707, doi:10.3762/bjnano.6.173

• size 0.02°). Attached functional groups have been analysed with Fourier transform infrared spectrometry (FTIR interferometer IR prestige-21 FTIR (model-8400S)) in the range of 400–4000 cm−1 by making calcined product pallets with KBr in a weight ratio of 1:10. ESR measurements were performed at room

Graphene quantum interference photodetector

• Mahbub Alam and
• Paul L. Voss

Beilstein J. Nanotechnol. 2015, 6, 726–735, doi:10.3762/bjnano.6.74

• interference (QI) photodetector was simulated in two regimes of operation. The structure consists of a graphene nanoribbon, Mach–Zehnder interferometer (MZI), which exhibits a strongly resonant transmission of electrons of specific energies. In the first regime of operation (that of a linear photodetector

• flux in one or both of the interferometer arms in the same MZI structure. Graphene QI photodetectors have several distinct advantages: they are of very small size, they do not require p- and n-doped regions, and they exhibit a high external quantum efficiency. Keywords: decoherence; graphene

• device structure that has attracted attention is the resonant tunneling diode, whose operation is based on quantum interference [10]. In graphene nanoribbons, a Mach–Zehnder interferometer (MZI) structure can be devised which gives the same transmittance pattern as that of a resonant tunneling diode for

In situ observation of biotite (001) surface dissolution at pH 1 and 9.5 by advanced optical microscopy

• Chiara Cappelli,
• Daniel Lamarca-Irisarri,
• Jordi Camas,
• F. Javier Huertas and
• Alexander E. S. Van Driessche

Beilstein J. Nanotechnol. 2015, 6, 665–673, doi:10.3762/bjnano.6.67

• -resolution phase shifting interferometer (PSI) that allows for the in situ measurement of extremely low surface dissolution (and growth) rates of minerals while submerged in aqueous solutions [26][27][28][29][30]. With the progress of these techniques our understanding of the mechanisms of the surface

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

• and drive lasers by using a modified knife-edge technique. An interferometer (NA, SIOS Meßtechnik, Ilmenau, Germany) tracked the position of the optics block as it was swept across a cantilever, and the sum signal from the photodiode was recorded. We inferred the spatial position of the focal spot

• . Acknowledgements We thank the Atelier de l’institut de production et robotique at EPFL for fabrication of the mechanical components, Aleksandra Radenovic for use of the spectrometer, and SCL-Sensor.tech. for use of the interferometer. This work was funded by the European Union’s Seventh Framework Programme FP7

Surface topography and contact mechanics of dry and wet human skin

• Alexander E. Kovalev,
• Kirstin Dening,
• Bo N. J. Persson and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2014, 5, 1341–1348, doi:10.3762/bjnano.5.147

• obtained by using a Hitachi TM3000 tabletop electron microscope (Hitachi High-Technologies Corp., Tokyo, Japan) at an accelerating voltage of 3 kV (Figure 1). 3D surface profiles of the positive replicas were acquired by using a white light interferometer NewView 6k (Zygo, Middlefield, CT, USA) with 5× and

Dry friction of microstructured polymer surfaces inspired by snake skin

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

Beilstein J. Nanotechnol. 2014, 5, 1091–1103, doi:10.3762/bjnano.5.122

• glass ball), its surface was repeatedly examined by white light interferometer (data not shown). As an indication for the maximum contact area occurring in our measurements we estimated the Hertzian contact area [42] of the glass sphere in contact with flat substrate according to the following

• gold-palladium (4:1) layer by using a high vacuum sputter coater Leica EM SCD500 (Leica Microsystems GmbH, Wetzlar, Germany). Additionally, for quick 3D surface observations a white-light interferometer (New View 6000, ZygoLOT, Darmstadt, Germany) without the sputter coating was used. As described in

• of microstructure. Arrows show sliding directions of each individual measurement. Exact geometry of each PGMS pattern (mean values and standard deviations) measured by white-light interferometer. λ: pitch dimension, A: periodicity of the structure, W: width of the structure and D: depth of the

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

• (Ra) of molds was measured with a white light interferometer (New View 6000, ZygoLOT, Darmstadt, Germany). For metrologic characterization of the surface microstructures, the image analysis software SigmaScanPro 5.0 (SPSS Inc., Chicago, USA) was used. Roughness (Ra) perpendicular to the lines of the

• (Ergo 5925 Elastomer, Tagelswangen, Switzerland). The roughness of the glass ball determined by a white light interferometer (NewView, ZygoLOT GmbH, Darmstadt, Germany) was Ra = 0.006 µm. The polymer surfaces were fixed on metallic sample holders by cyanoacrylate glue. To characterize frictional

Multiple regimes of operation in bimodal AFM: understanding the energy of cantilever eigenmodes

• Daniel Kiracofe,
• Arvind Raman and
• Dalia Yablon

Beilstein J. Nanotechnol. 2013, 4, 385–393, doi:10.3762/bjnano.4.45

• , interferometer based AFMs, which do not suffer from these calibration problems, may become more attractive than optical lever (photodiode) based AFMs. Conclusion We have shown experimentally that there are multiple distinct imaging regimes in bimodal AFM. The different states were identified by contrast

Effect of deposition temperature on the structural and optical properties of chemically prepared nanocrystalline lead selenide thin films

• Anayara Begum,
• Amir Hussain and
• Atowar Rahman

Beilstein J. Nanotechnol. 2012, 3, 438–443, doi:10.3762/bjnano.3.50

• ) in the wavelength range 360–900 nm. The thickness of the PbSe thin films was measured by the multiple beam interferometer technique. Results and Discussion Film growth A PbSe thin film is formed when the ionic product of Pb2+ and Se2− ions exceeds the solubility product of PbSe (≈10−38 at 300 K) [16

Nano-FTIR chemical mapping of minerals in biological materials

• Sergiu Amarie,
• Paul Zaslansky,
• Yusuke Kajihara,
• Erika Griesshaber,
• Wolfgang W. Schmahl and
• Fritz Keilmann

Beilstein J. Nanotechnol. 2012, 3, 312–323, doi:10.3762/bjnano.3.35

• and spectral analysis of the backscattered light is by an asymmetric Michelson interferometer that generates, by online Fourier transformation, infrared amplitude and phase spectra simultaneously; a switchable reference path ensures an absolute quantification of backscattering [3]. Note that while

• spectrally integrated mode of nano-FTIR is also introduced in this study. It employs a fixed interferometer setting at a (free-induction-decay) [2] fringe maximum (ca. 150–300 fs delay). The detector amplitude signal then represents the background-suppressed near-field signal response averaged over a wide

Mechanical characterization of carbon nanomembranes from self-assembled monolayers

• Xianghui Zhang,
• André Beyer and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2011, 2, 826–833, doi:10.3762/bjnano.2.92

• one side. The Young’s modulus and the prestress are then calculated from the obtained pressure–deflection relationship. The deflection is usually monitored with an optical microscope, either by viewing the membrane from the side [12] or by using a laser interferometer [13]. Both methods have a