Bulk chemical composition contrast from attractive forces in AFM force spectroscopy

• Dorothee Silbernagl,
• Media Ghasem Zadeh Khorasani,
• Natalia Cano Murillo,
• Anna Maria Elert and
• Heinz Sturm

Beilstein J. Nanotechnol. 2021, 12, 58–71, doi:10.3762/bjnano.12.5

• turn generate oscillating dipoles in an adjacent body. The response of a specific material in an oscillating electromagnetic field E(f) is described by the dielectric constant εr(f) which can be extracted from the absorption spectrum of the material. Hence, how materials (e.g., the sample (S) and the

• tip (T)) interact in a medium (m) is defined by the difference in the dielectric responses. The Hamaker coefficient AHam can be derived from the relative differences of the dielectric constant εS(f), εT(f), and εm(f), summed up over all the frequencies at which the fluctuations can occur (UV–vis–IR

Kondo effects in small-bandgap carbon nanotube quantum dots

• Patryk Florków,
• Damian Krychowski and
• Stanisław Lipiński

Beilstein J. Nanotechnol. 2020, 11, 1873–1890, doi:10.3762/bjnano.11.169

• effects of interaction play a more fundamental role. Carbon nanotubes are quasi one-dimensional systems, and the role of correlations further increases in quantum dots due to additional confinement. Of importance is also the low dielectric constant, which is especially low in suspended nanotubes [36]. A

Absorption and photoconductivity spectra of amorphous multilayer structures

• Oxana Iaseniuc and
• Mihail Iovu

Beilstein J. Nanotechnol. 2020, 11, 1757–1763, doi:10.3762/bjnano.11.158

• , Nt is the concentration of traps, e is the electron charge, µ is the drift mobility, ε is the dielectric constant, t = Δ/(kBT) (Δ is the parameter of the trap distribution, kB is the Boltzmann constant, T is the absolute temperature), V is the applied voltage, and d is the sample thickness. The

Controlling the electronic and physical coupling on dielectric thin films

• Philipp Hurdax,
• Michael Hollerer,
• Larissa Egger,
• Georg Koller,
• Xiaosheng Yang,
• Anja Haags,
• Serguei Soubatch,
• Frank Stefan Tautz,
• Mathias Richter,
• Alexander Gottwald,
• Peter Puschnig,
• Martin Sterrer and
• Michael G. Ramsey

Beilstein J. Nanotechnol. 2020, 11, 1492–1503, doi:10.3762/bjnano.11.132

• considered. The capacitor model and the interlayer dielectric constant The behavior observed in the ARUPS series of Figure 4 and Figure 5 is consistent with the predictions from the capacitor model expressed in Equation 1. Figure 6a depicts the relationship between the SOMO intensity (ISOMO) and the work

• monolayer and thus the charge density (σ) on the surface. For the capacitor model to be predictive and quantitative for ultrathin decoupling layers, a realistic value for their dielectric constant (εr) is required. This can be estimated from a molecular dosing series, such as in Figure 5. Figure 6b shows

• work function upon adsorption of the molecules (ΔΦ = Φmol − ΦMgO, where Φmol is the final work function after adsorption of the molecules) is very well described by electrostatics with a simple capacitor model given by where σ is the average charge density in the molecular film, εr is the dielectric

Structural and electronic properties of SnO₂ doped with non-metal elements

• Jianyuan Yu,
• Yingeng Wang,
• Yan Huang,
• Xiuwen Wang,
• Jing Guo,
• Jingkai Yang and
• Hongli Zhao

Beilstein J. Nanotechnol. 2020, 11, 1321–1328, doi:10.3762/bjnano.11.116

• dielectric constant is εr = 0, the concentration of positive and negative charges is the same, and positive and negative charges are free to move. When the probability of collision of free electrons in a solid is 0, the dielectric function is where ωp is the plasma frequency. ωp is the intrinsic

Role of redox-active axial ligands of metal porphyrins adsorbed at solid–liquid interfaces in a liquid-STM setup

• Thomas Habets,
• Sylvia Speller and
• Johannes A. A. W. Elemans

Beilstein J. Nanotechnol. 2020, 11, 1264–1271, doi:10.3762/bjnano.11.110

• and 2.03, respectively. A different dielectric constant may lead to a different potential decay at the interfaces, which in turn may influence the reaction rates. However, since the difference in dielectric constant between the two solvents is small, we propose the first explanation as being more

High permittivity, breakdown strength, and energy storage density of polythiophene-encapsulated BaTiO₃ nanoparticles

• Adnanullah Khan,
• Amir Habib and
• Adeel Afzal

Beilstein J. Nanotechnol. 2020, 11, 1190–1197, doi:10.3762/bjnano.11.103

• exhibit irregular surface profile, which confirms the occurrence of sub-micrometer clusters and nanoscale particles on the surface. The permittivity or dielectric constant (ε′), loss tangent (tan δ), dielectric loss (ε″), and ac conductivity (σac) of the synthesized materials are measured as a function of

• two phases prevent the free-charge accumulation at the interface and, therefore, improve the breakdown strength. Furthermore, in situ oxidative polymerization of PTh on BTO surfaces allows for the inclusion of 90 wt % BTO, which results in a high dielectric constant. This means that the tremendous

• increase in the energy storage density of core–shell BTO-PTh nanoparticles is due to the combined effect of high dielectric constant (ε′) and improved breakdown strength (Eb). These results are noteworthy considering the previous examples of BTO-polymer composite dielectric materials. Table 1 offers a

Nonadiabatic superconductivity in a Li-intercalated hexagonal boron nitride bilayer

• Kamila A. Szewczyk,
• Izabela A. Domagalska,
• Artur P. Durajski and
• Radosław Szczęśniak

Beilstein J. Nanotechnol. 2020, 11, 1178–1189, doi:10.3762/bjnano.11.102

• result is radically different from the data obtained for graphene/SiO2 [33]. In addition, hBN monolayers exhibit a high temperature stability, a low dielectric constant (ε = 3–4), and a high thermal conductivity [34]. The band gap of hBN is about 5.9 eV [35]. Furthermore, which is also important, hBN is

Excitonic and electronic transitions in Me–Sb₂Se₃ structures

• Nicolae N. Syrbu,
• Victor V. Zalamai,
• Ivan G. Stamov and
• Stepan I. Beril

Beilstein J. Nanotechnol. 2020, 11, 1045–1053, doi:10.3762/bjnano.11.89

• the reflection spectra for both Е||с and Е⟂с polarization cases at 300 K. The calculations showed that for the polarization Е||с the background dielectric constant (εb) is equal to 7.5, the energy of the transversal exciton (ωТ) is 1.192 eV, the longitudinal-transversal splitting (ωLT) is 15 meV, the

• effective mass (μ*) is calculated for the excitons A, B, C and D. For excitons A and B when the background dielectric constant is εb = 7.5 and the binding energy is Ry = 130–136 meV the reduced exciton mass is μ* = 0.56m0. For the exciton series C at εb = 7.5 and at the binding energy Ry = 82 meV, the

A new photodetector structure based on graphene nanomeshes: an ab initio study

• Babak Sakkaki,
• Hassan Rasooli Saghai,
• Ghafar Darvish and
• Mehdi Khatir

Beilstein J. Nanotechnol. 2020, 11, 1036–1044, doi:10.3762/bjnano.11.88

• permittivity and system volume, respectively. The relative dielectric constant, εr, is related to the susceptibility, χ, as [26][27]: The photocurrent is calculated by first-order perturbation theory in the framework of the Born approximation. In short, light–electron interaction is added to the Hamiltonian as

High dynamic resistance elements based on a Josephson junction array

• Konstantin Yu. Arutyunov and
• Janne S. Lehtinen

Beilstein J. Nanotechnol. 2020, 11, 417–420, doi:10.3762/bjnano.11.32

• connected in series, each being a Al–AlOx–Al junction with a gap of about 400 µV. The charging energy, Ec = e2/2C, of each SIS contact (considering it to be a plate capacitor with dielectric constant ε ≈ 10, area 100 × 100 nm and distance between plates ≈2 nm) is about two orders of magnitude higher than

Advanced hybrid nanomaterials

• Andreas Taubert,
• Fabrice Leroux,
• Pierre Rabu and
• Verónica de Zea Bermudez

Beilstein J. Nanotechnol. 2019, 10, 2563–2567, doi:10.3762/bjnano.10.247

• as functionalized films with high dielectric constant, or, in the case of optical applications, this consists also in embedding different types of nanoparticles. In the first example, “Co-intercalated layered double hydroxides as thermal and photo-oxidation stabilizers for polypropylene”, the

• fire retardancy and gas permeation in a low molecular weight epoxy resin [28]. Regarding specific applications, the dielectric properties were investigated by broadband dielectric spectroscopy (BDS) in “Nanocomposite–parylene C thin films with high dielectric constant and low losses for future organic

Nonlinear absorption and scattering of a single plasmonic nanostructure characterized by x-scan technique

• Tushar C. Jagadale,
• Dhanya S. Murali and
• Shi-Wei Chu

Beilstein J. Nanotechnol. 2019, 10, 2182–2191, doi:10.3762/bjnano.10.211

• , the backscattering decay is by cubic order larger than the absorption decay. One possible reason could be that scattering is proportional to the square of the variation of the dielectric constant, while absorption is linearly proportional to the dielectric constant. Within the dipole approximation

• , the absorption and scattering cross sections of a plasmonic nanosphere can be determined by classical Mie theory as: where, k is the wave vector, r is the radius of the particle, εp is the dielectric constant of the particle and εm is the dielectric constant of the surrounding medium. Upon irradiation

BergaCare SmartLipids: commercial lipophilic active concentrates for improved performance of dermal products

• Florence Olechowski,
• Rainer H. Müller and
• Sung Min Pyo

Beilstein J. Nanotechnol. 2019, 10, 2152–2162, doi:10.3762/bjnano.10.208

• the skin even under mechanical stress is beneficial to fight pollution factors. The lipid particles adhere onto the skin as any nanosized particle does and form a film. This film formation can be followed by measuring the dielectric constant of the skin, using a Corneometer® (Courage + Khazaka

• Electronic GmbH, Germany) [26]. The probe determines the dielectric constant, D, of the skin through a condenser in the probe. An insulator medium in the condenser reduces the measured D value. For example, D is 0 for a complete insulator (vacuum), about 5 for lipids and organic liquids, and 80 for pure

• remain on the skin (right arm). Determination of the relative film thickness by measuring the dielectric constant D on skin. Probe readings of untreated skin and skin with applied increasing concentration of lipid particle suspension; reproduced with permission from [27], copyright 2013 Euro Cosmetics

Fabrication and characterization of Si_1−xGe_x nanocrystals in as-grown and annealed structures: a comparative study

• Muhammad Taha Sultan,
• Adrian Valentin Maraloiu,
• Ionel Stavarache,
• Jón Tómas Gudmundsson,
• Andrei Manolescu,
• Valentin Serban Teodorescu,
• Magdalena Lidia Ciurea and
• Halldór Gudfinnur Svavarsson

Beilstein J. Nanotechnol. 2019, 10, 1873–1882, doi:10.3762/bjnano.10.182

• interface traps (known as Pb-type defects). These interface traps produce scattering centers that can affect the mobility of charge carriers, thus altering the transport properties [11]. Moreover, sharp interfaces with an abrupt change in the dielectric constant or thermal expansion coefficients give rise

Prestress-loading effect on the current–voltage characteristics of a piezoelectric p–n junction together with the corresponding mechanical tuning laws

• Wanli Yang,
• Shuaiqi Fan,
• Yuxing Liang and
• Yuantai Hu

Beilstein J. Nanotechnol. 2019, 10, 1833–1843, doi:10.3762/bjnano.10.178

• = e2/(cε). In the above, strain S and electric field E can be expressed as S = du/dx and E = −dϕ/dx, in which u and ϕ are displacement and electric potential, respectively. c, e and ε are elastic, piezoelectric and dielectric constant, respectively. The one-dimensional Gauss’s law of a piezoelectric p

Materials nanoarchitectonics at two-dimensional liquid interfaces

• Katsuhiko Ariga,
• Michio Matsumoto,
• Taizo Mori and
• Lok Kumar Shrestha

Beilstein J. Nanotechnol. 2019, 10, 1559–1587, doi:10.3762/bjnano.10.153

• categorized as interfacial environments with certain degrees of freedom of molecular mobility (dynamism). These interfaces with liquids have several intrinsic features: (i) They are environments of two different phases; (ii) they exhibit a discontinuous change of the dielectric constant; (iii) they are highly

• revealed that large binding constants can be obtained when the binding site locates in the phase of the lower dielectric constant. In contrast, when the binding site was located to be deep in the phase of the higher dielectric constant, the binding constants were calculated to decrease significantly

Tailoring the magnetic properties of cobalt ferrite nanoparticles using the polyol process

• Malek Bibani,
• Romain Breitwieser,
• Alex Aubert,
• Vincent Loyau,
• Silvana Mercone,
• Souad Ammar and
• Fayna Mammeri

Beilstein J. Nanotechnol. 2019, 10, 1166–1176, doi:10.3762/bjnano.10.116

• backbone and a higher dielectric constant (εr(TriEG) = 23.7 vs εr(TetEG) = 20.4) while the latter exhibits a larger molecular weight and is assumed to be a little more polar (µTetEG = 5.84 D vs µTriEG = 5.58 D) [28]. Regardless of reaction time and composition, we observe that the NP diameter is higher

• when tetraethylene glycol is used instead of triethylene glycol. Dipolar moment and dielectric constant of the two molecules are very similar and we can assume that they both exhibit the same strength to dissolve the ionic precursors. TetEG has a longer backbone than TriEG and can chelate bigger

CuInSe₂ quantum dots grown by molecular beam epitaxy on amorphous SiO₂ surfaces

• Henrique Limborço,
• Pedro M.P. Salomé,
• Rodrigo Ribeiro-Andrade,
• Jennifer P. Teixeira,
• Nicoleta Nicoara,
• Kamal Abderrafi,
• Joaquim P. Leitão,
• Juan C. Gonzalez and
• Sascha Sadewasser

Beilstein J. Nanotechnol. 2019, 10, 1103–1111, doi:10.3762/bjnano.10.110

• energy for the QD [48] and QW [49] can be calculated as: where Eg is the CIS low-temperature bandgap energy, h is the Planck constant, me is the effective conduction-band mass, mh is the effective valence-band mass, e is the rest electron charge, ε is the CIS dielectric constant and Ex is the exciton

Influence of dielectric layer thickness and roughness on topographic effects in magnetic force microscopy

• Alexander Krivcov,
• Jasmin Ehrler,
• Marc Fuhrmann,
• Tanja Junkers and
• Hildegard Möbius

Beilstein J. Nanotechnol. 2019, 10, 1056–1064, doi:10.3762/bjnano.10.106

• nanoparticle diameter) resulting in a positive phase shift: with A being the effective capacitive area, z the lift height, d the nanoparticle diameter, VCPD the contact potential difference between tip and substrate, Q the quality factor, k the spring constant of the cantilever, and ε0 the dielectric constant

• capacitive coupling of the tip with the substrate beneath the dielectric layer. The effective thickness is calculated as follows: εR represents the dielectric constant and tl the real film thickness of the dielectric layer. The dielectric constant for the layer used in this work is 3.1 [21]. Figure 3

• silicon substrates at 3000 rpm using a closed-system spin-coater with rotating lid (BLE). Bisphenol A-epichlorohydrin resin was used as dielectric layer. The resin is the hard component of AR-P 5910 resist (Allresist) with a dielectric constant of 3.1 [21]. The thickness was varied by different dilutions

Revisiting semicontinuous silver films as surface-enhanced Raman spectroscopy substrates

• Malwina Liszewska,
• Bogusław Budner,
• Małgorzata Norek,
• Bartłomiej J. Jankiewicz and
• Piotr Nyga

Beilstein J. Nanotechnol. 2019, 10, 1048–1055, doi:10.3762/bjnano.10.105

• dielectric constant of the metal, surrounding dielectric, shape and size of the nanostructure, and its orientation with respect to the electric component of the electromagnetic field [1][2]. At resonance, the electric field near the surface of metallic nanostructures can be greatly enhanced and localized in

Structural and optical properties of penicillamine-protected gold nanocluster fractions separated by sequential size-selective fractionation

• Xiupei Yang,
• Zhengli Yang,
• Fenglin Tang,
• Jing Xu,
• Maoxue Zhang and
• Martin M. F. Choi

Beilstein J. Nanotechnol. 2019, 10, 955–966, doi:10.3762/bjnano.10.96

• the solution, the solubility of AuNCs in the mixed solvent was lowered due to the low dielectric constant of acetone, resulting in the precipitation of relatively large-sized clusters. The deposit could then be separated from the solution by centrifugation. Four fractions (F36%, F54%, F72%, and F90

Review of time-resolved non-contact electrostatic force microscopy techniques with applications to ionic transport measurements

• Aaron Mascaro,
• Yoichi Miyahara,
• Tyler Enright,
• Omur E. Dagdeviren and
• Peter Grütter

Beilstein J. Nanotechnol. 2019, 10, 617–633, doi:10.3762/bjnano.10.62

• dielectric constant (εr > 10), which is similar to those found in many solid ionic conductors such as LiFePO4 and LiCoO2, and for its low electronic conductivity and lack of mobile ions. This experiment is therefore a reliable validation of the z-dependence of the tip–sample capacitance expected for actual

Biomimetic synthesis of Ag-coated glasswing butterfly arrays as ultra-sensitive SERS substrates for efficient trace detection of pesticides

• Guochao Shi,
• Mingli Wang,
• Yanying Zhu,
• Yuhong Wang,
• Xiaoya Yan,
• Xin Sun,
• Haijun Xu and
• Wanli Ma

Beilstein J. Nanotechnol. 2019, 10, 578–588, doi:10.3762/bjnano.10.59

• set to 1 nm × 1 nm × 1 nm. The dielectric function of a metal is a complex entity as a function of the wavelength. Therefore, the infinite-frequency relative dielectric constant and the zero-frequency relative dielectric constant of Ag were set according to the Gai’s work [36]. In order to simulate as

Mo-doped boron nitride monolayer as a promising single-atom electrocatalyst for CO₂ conversion

• Qianyi Cui,
• Gangqiang Qin,
• Weihua Wang,
• Lixiang Sun,
• Aijun Du and
• Qiao Sun

Beilstein J. Nanotechnol. 2019, 10, 540–548, doi:10.3762/bjnano.10.55

• solvent environment [60], and the dielectric constant was 78.54. To construct the modes, we first built a periodic 5 × 5 BN supercell, whose vacuum region was 15 Å along the z-direction. The single TM atoms were doped at the boron vacancy sites [45]. All of the structures were completely optimized in a