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

• ], and ε = 9.3–16ε0 (where ε0 is the vacuum electrical permittivity) [52][55][56]. The experimentally determined peak emission energies are also plotted, as a function of Rc for each sample. Clearly, the obtained values are in agreement with the emission from the quantum-confined energy levels in CIS

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

• parameters. Theoretically, , where ε is the permittivity and V is the applied voltage, and is the effective tip radius. The oscillation amplitude for both experiments was 6 nm, thus the x-axis is the average tip–sample separation and the zero-point was chosen as the point when the oscillation stopped due to

Nanocomposite–parylene C thin films with high dielectric constant and low losses for future organic electronic devices

• Marwa Mokni,
• Gianluigi Maggioni,
• Abdelkader Kahouli,
• Sara M. Carturan,
• Walter Raniero and
• Alain Sylvestre

Beilstein J. Nanotechnol. 2019, 10, 428–441, doi:10.3762/bjnano.10.42

• of the permittivity. In particular, β-relaxation is affected by the addition of nanoparticles as well as the dissipation factor, which is even improved. A dielectric constant of 5 ± 1 with a dissipation factor of less than 0.045 in the range from 0.1 Hz to 1 MHz is obtained for a 2.7 µm thick NCPC

• develop NCPCs is the integration as gate insulating layer in such applications. A sufficiently high capacitance Ci of the gate insulating material is required for optimizing performances in OFETs [3]. Ci is given by: where ε0 is the vacuum permittivity (8.85 × 10−12 F·m−1), t the thickness of the

• dielectric, S the surface of electrodes and ε’ (often named k in the industry of microelectronics) is the dielectric constant (more rigorously called relative permittivity). As seen by this equation, the insulating gate capacitance Ci is directly proportional to ε’. Typically, for parylene C ε’ = 3.15 (at 1

Electromagnetic analysis of the lasing thresholds of hybrid plasmon modes of a silver tube nanolaser with active core and active shell

• Denys M. Natarov,
• Trevor M. Benson and
• Alexander I. Nosich

Beilstein J. Nanotechnol. 2019, 10, 294–304, doi:10.3762/bjnano.10.28

• εmet(λ) = −εhost where εhost > 0 is the relative dielectric permittivity of the host medium – see [1][2] for details. If the host medium is air, then the corresponding wavelength is found in the ultraviolet range for silver and in the green range for gold where the bulk losses in metals are

• modes. Note also that there exist other LEP-like formulations aimed at the extraction of mode threshold [28][29][30][31][32]; some of them differ from LEP only by the choice of the material-gain parameter, which can be the imaginary part of the dielectric permittivity (because Im εa = 2αγ, where α is

• transcendental Equation 5 numerically, we use an iterative Newton-type algorithm that needs some initial guess values of the unknown wavelength λ and threshold gain γ. Because of the strong dispersion of the dielectric permittivity of silver, it is convenient to take these initial values after plotting the color

Magnetic-field sensor with self-reference characteristic based on a magnetic fluid and independent plasmonic dual resonances

• Kun Ren,
• Xiaobin Ren,
• Yumeng He and
• Qun Han

Beilstein J. Nanotechnol. 2019, 10, 247–255, doi:10.3762/bjnano.10.23

• magnetic fluid. The background metal in the grey part is silver, the complex permittivity of which is characterized by the well-known Drude model: , where ε∞ = 3.7 is the permittivity at infinite angular frequency, the bulk plasma frequency is ωp = 1.38 × 1016 Hz, the damping frequency of the oscillations

Interaction of Te and Se interlayers with Ag or Au nanofilms in sandwich structures

• Arkadiusz Ciesielski,
• Lukasz Skowronski,
• Marek Trzcinski,
• Ewa Górecka,
• Wojciech Pacuski and
• Tomasz Szoplik

Beilstein J. Nanotechnol. 2019, 10, 238–246, doi:10.3762/bjnano.10.22

• migrate only in silver. The Te concentration curve clearly suggests that this migration is an effect of the segregation of Te atoms in the silver structure. The differences in crystallinity, as well as the migration process, strongly influence the optical parameters of Ag and Au. In the permittivity of Ag

• deposited on either Te or Se, additional plasmonic bands originating from grain boundary segregation or diffusion occur, while for the Au layer, such resonances were not pronounced. In the permittivity of both materials, the intensity of the interband transition peaks is strongly altered, possibly due to

• the nano-alloy formation, but more likely due to the microstrain on metal grains. Keywords: diffusion; gold; microstrain; nanocrystallinity; permittivity; plasmonics; segregation; selenium; silver; tellurium; Introduction In recent years, there has been growing interest in layered, sandwich-like

Threshold voltage decrease in a thermotropic nematic liquid crystal doped with graphene oxide flakes

• Mateusz Mrukiewicz,
• Krystian Kowiorski,
• Paweł Perkowski,
• Rafał Mazur and
• Małgorzata Djas

Beilstein J. Nanotechnol. 2019, 10, 71–78, doi:10.3762/bjnano.10.7

• the tilt angle θ is small. When the voltage is above Uth, we start to observe the increase of θ [4]. The complete reorientation of the director n, θ = 90°, occurs at higher voltages U > Uth. The reorientation is caused by the anisotropy of the electric permittivity where ε|| and is the electric

• permittivity measured along the directions parallel and perpendicular to n, respectively. In the case of positive electric anisotropy (Δε > 0), the director is forced to align along the electric field. One of the most efficient methods to reduce the threshold voltage in nematic liquid crystals for high electro

• ) experimental technique. On one hand, in EO we measure the intensity of light passing through the cell between crossed polarizers as a function of an applied voltage. On the other hand, DS is based on measurements of electric permittivity ε at a given frequency under different bias (dc) electric fields. These

Electrostatic force microscopy for the accurate characterization of interphases in nanocomposites

• Diana El Khoury,
• Richard Arinero,
• Jean-Charles Laurentie,
• Mikhaël Bechelany,
• Michel Ramonda and
• Jérôme Castellon

Beilstein J. Nanotechnol. 2018, 9, 2999–3012, doi:10.3762/bjnano.9.279

• “calibrating” the EFM technique for future interphase studies. EFM was demonstrated to be able to discriminate between alumina and silicon dioxide interphase layers of 50 and 100 nm thickness deposited over polystyrene spheres and different types of matrix materials. Consistent permittivity values were also

• deduced by comparison of experimental data and numerical simulations, as well as the interface state of silicone dioxide layers. Keywords: atomic force microscopy; building-block materials; dielectric permittivity; electrostatic force microscopy; finite element simulation; interphases; nanocomposites

• filler. For instance, although the inorganic filler usually displays higher permittivity values than the polymer, the resulting nanofiller mixture in the matrix presents, at low nanofiller concentrations, a surprisingly lower dielectric constant than that of the two mixture components [10][11][12][13

In situ characterization of nanoscale contaminations adsorbed in air using atomic force microscopy

• Jesús S. Lacasa,
• Lisa Almonte and
• Jaime Colchero

Beilstein J. Nanotechnol. 2018, 9, 2925–2935, doi:10.3762/bjnano.9.271

• , h is the total thickness of the dielectric films on tip and sample, ε0 is the dielectric permittivity of vacuum and ε is the relative dielectric constant [43][44][45][46]. For a purely metallic system in air or vacuum were no dielectric layer is present (h = 0), the expression simplifies to C″(d

Time-resolved universal temperature measurements using NaYF₄:Er³⁺,Yb³⁺ upconverting nanoparticles in an electrospray jet

• Kristina Shrestha,
• Arwa A. Alaulamie,
• Ali Rafiei Miandashti and
• Hugh H. Richardson

Beilstein J. Nanotechnol. 2018, 9, 2916–2924, doi:10.3762/bjnano.9.270

• permittivity and permeability of water, l is an integer, and a is the radius of the WGM cavity [39][40]. The plot of wavenumbers of WGM peaks vs as a function of l + 1/2 is shown in Figure 6B. The slope from a linear fit is used to calculate the cavity radius of 2.87 ± 0.02 μm. The Q-factor of the WGM cavity

Site-controlled formation of single Si nanocrystals in a buried SiO₂ matrix using ion beam mixing

• Xiaomo Xu,
• Thomas Prüfer,
• Daniel Wolf,
• Hans-Jürgen Engelmann,
• Lothar Bischoff,
• René Hübner,
• Karl-Heinz Heinig,
• Wolfhard Möller,
• Stefan Facsko,
• Johannes von Borany and
• Gregor Hlawacek

Beilstein J. Nanotechnol. 2018, 9, 2883–2892, doi:10.3762/bjnano.9.267

• temperature, the diameter of an individual Si NC, 2rNC, has to be smaller than 5.7 nm. The other factors are the unit charge e and ε0 and εr = 3.9 are the vacuum permittivity and the relative permittivity of silicon dioxide, respectively. Recently, advanced lithographic methods [21] and directed self-assembly

Contactless photomagnetoelectric investigations of 2D semiconductors

• Marian Nowak,
• Marcin Jesionek,
• Barbara Solecka,
• Piotr Szperlich,
• Piotr Duka and
• Anna Starczewska

Beilstein J. Nanotechnol. 2018, 9, 2741–2749, doi:10.3762/bjnano.9.256

• ] (ε0ε/we)Vg, where ε0 and ε are the permittivity of free space and the used dielectric, respectively; e is the electron charge; and w is the thickness of the dielectric. The authors of [35] provided the theoretical description of the current compact model of graphene field-effect transistors. In our

• case, the energy position of the Fermi level of graphene was modulated by the field effect through the 170 μm thick PET foil. The relative permittivity of PET is ε = 3.5 at 71 kHz [42]. Figure 6b shows the PME voltage induced in the measuring coil as a function of the back-gate bias. The inserts depict

Polarization-dependent strong coupling between silver nanorods and photochromic molecules

• Gwénaëlle Lamri,
• Alessandro Veltri,
• Jean Aubard,
• Pierre-Michel Adam,
• Nordin Felidj and
• Anne-Laure Baudrion

Beilstein J. Nanotechnol. 2018, 9, 2657–2664, doi:10.3762/bjnano.9.247

• approximation: where and refer to the polarization of the incoming light, Vp is the volume of the particle, ε1 is silver permittivity, ε2 is the permittivity of the host medium, deduced by the ellipsometric measurements; while and are geometrical factors given by: Here e is the eccentricity calculated as

Impact of the anodization time on the photocatalytic activity of TiO₂ nanotubes

• Jesús A. Díaz-Real,
• Geyla C. Dubed-Bandomo,
• Juan Galindo-de-la-Rosa,
• Luis G. Arriaga,
• Janet Ledesma-García and
• Nicolas Alonso-Vante

Beilstein J. Nanotechnol. 2018, 9, 2628–2643, doi:10.3762/bjnano.9.244

• the Mott–Schottky equation (Equation 2): where Csc is the capacitance of the space-charge region, ND is the density of dopant atoms (cm−3), Efb is the flat-band potential, q is the elementary charge (1.602 × 10−19 C), ε0 is the vacuum permittivity (8.85 × 10−14 F·cm−1), and ε (42, [70]) is the

Enhancement of X-ray emission from nanocolloidal gold suspensions under double-pulse excitation

• Wei-Hung Hsu,
• Frances Camille P. Masim,
• Armandas Balčytis,
• Hsin-Hui Huang,
• Tetsu Yonezawa,
• Aleksandr A. Kuchmizhak,
• Saulius Juodkazis and
• Koji Hatanaka

Beilstein J. Nanotechnol. 2018, 9, 2609–2617, doi:10.3762/bjnano.9.242

• was revealed that the volume around gold nanoparticles where the permittivity is near zero, ε ≈ 0, accounts for the strongest absorption, which leads to the effective enhancements of X-ray emission. Keywords: double pulse; gold nanoparticles; intense femtosecond laser; plasma; water; X-ray

• [26], respectively. Theory: Epsilon-Near-Zero (ENZ)-Material A strong generation of X-rays is related to a large amount of absorbed energy and a high temperature [3][4]. In terms of relative permittivity (dielectric constant), εr, a transparent medium (water) with colloidal gold nanoparticles

• represents an effective medium with an overall positive real part of the permittivity. Upon excitation, the material is approaching dielectric breakdown and a state of εr ≈ 0 (epsilon-near-zero (ENZ) state; ). Under the ENZ condition, the strongest absorption takes place [36][37]: Here, εi is the intrinsic

Au–Si plasmonic platforms: synthesis, structure and FDTD simulations

• Anna Gapska,
• Marcin Łapiński,
• Paweł Syty,
• Wojciech Sadowski,
• Józef E. Sienkiewicz and
• Barbara Kościelska

Beilstein J. Nanotechnol. 2018, 9, 2599–2608, doi:10.3762/bjnano.9.241

• , characterized by a large number of free electrons, which leads to a high plasma frequency and a negative real permittivity over a wide range of frequencies. Taking into account the existence of a eutectic from Au and Si, which gives the possibility of producing metal nanostructures on Si, and the aforementioned

Interaction-induced zero-energy pinning and quantum dot formation in Majorana nanowires

• Samuel D. Escribano,
• Alfredo Levy Yeyati and
• Elsa Prada

Beilstein J. Nanotechnol. 2018, 9, 2171–2180, doi:10.3762/bjnano.9.203

• charges that emerge in the electrostatic environment. We compute the electrostatic potential using Poisson’s equation where is the non-homogeneous dielectrical permittivity of the entire system and is the quantum and thermal average of the charge density of the nanowire obtained with Equation 1. The

• and the unavoidable presence of disorder [38]. If this is the case, it is then characterized by a finite effective dielectric permittivity which depends on the SC shell width as well as its composition, as we show in Section 1 of Supporting Information File 1. Some experiments [39] have reported that

• for ultrathin metallic layers (ca. 5–10 nm) it is of the order of εSC ≈ 100. For these values, as we show in the next section, we find a repulsive environment, i.e., an environment the effective permittivity of which is smaller than that of the wire so that the bound charges that arise at the

Absence of free carriers in silicon nanocrystals grown from phosphorus- and boron-doped silicon-rich oxide and oxynitride

• Daniel Hiller,
• Julian López-Vidrier,
• Keita Nomoto,
• Michael Wahl,
• Wolfgang Bock,
• Tomáš Chlouba,
• František Trojánek,
• Sebastian Gutsch,
• Margit Zacharias,
• Dirk König,
• Petr Malý and
• Michael Kopnarski

Beilstein J. Nanotechnol. 2018, 9, 1501–1511, doi:10.3762/bjnano.9.141

• dopant ionization energies increase, which decreases exponentially the free carrier density [1]. If a doped Si-nanovolume is embedded in a matrix of lower permittivity (e.g., a dielectric), the dopant charge is not fully screened in the silicon and a Coulomb interaction with its image charge in the

Tailoring polarization and magnetization of absorbing terahertz metamaterials using a cut-wire sandwich structure

• Hadi Teguh Yudistira,
• Shuo Liu,
• Tie Jun Cui and
• Han Zhang

Beilstein J. Nanotechnol. 2018, 9, 1437–1447, doi:10.3762/bjnano.9.136

• (SZU), Shenzhen 518060, China Mechanical Engineering Program, Institut Teknologi Sumatera (ITERA), Lampung 35365, Indonesia, State Key Laboratory of Milimeter Waves, Southeast University, Nanjing 210096, China 10.3762/bjnano.9.136 Abstract The permittivity and permeability of a cut-wire sandwich

• structure can be controlled by laterally shifting the upper and lower layers. The use of this process for designing specific application-oriented devices may lack clear-cut guidelines because the lateral misalignment will significantly change the permittivity and permeability simultaneously. Therefore, in

• smaller than the wavelength of the terahertz electromagnetic (EM) wave. Thus, such structures can be considered a homogeneous medium from the perspective of the EM wave. The existence of multiple metallic structures in a device may affect the EM properties, such as permittivity and permeability. Several

Formation and development of nanometer-sized cybotactic clusters in bent-core nematic liquid crystalline compounds

• Yuri P. Panarin,
• Sithara P. Sreenilayam,
• Jagdish K. Vij,
• Anne Lehmann and
• Carsten Tschierske

Beilstein J. Nanotechnol. 2018, 9, 1288–1296, doi:10.3762/bjnano.9.121

• clusters (NcybC) of the SmC type as explained above. The second compound, BCN84, has two asymmetrical alkyl chains of different lengths and is of the same molar mass as BCN66. The dielectric permittivity measurements were carried out using a broadband alpha high-resolution dielectric analyzer (Novocontrol

• correlations among the neighboring molecules were revealed and the cybotactic clusters were established [35][36][48]. This was the first successful attempt for determining the cluster size by using the Maier–Meier equations using dielectric parameters such as anisotropic permittivity and the anisotropic

• individual molecular modes [30][31]. Temperature dependence of the dielectric properties The dielectric spectra of BCN66 were analyzed by using the WINFIT software of Novocontrol GmbH. The dielectric data on the complex permittivity were fitted to the Havriliak–Negami (H–N) equation (Equation 1). where ε∞ is

Surface characterization of nanoparticles using near-field light scattering

• Eunsoo Yoo,
• Yizhong Liu,
• Chukwuazam A. Nwasike,
• Sebastian R. Freeman,
• Brian C. DiPaolo,
• Bernardo Cordovez and
• Amber L. Doiron

Beilstein J. Nanotechnol. 2018, 9, 1228–1238, doi:10.3762/bjnano.9.114

• . On the basis of the Stogryn model, the solution dielectric constant (permittivity), εs, is inversely proportional to the solute concentration, C [43][44]. As the solute concentration C increases, the solution dielectric constant εs decreases, thus the particle polarizability α also decreases [45

A novel copper precursor for electron beam induced deposition

• Caspar Haverkamp,
• George Sarau,
• Mikhail N. Polyakov,
• Ivo Utke,
• Marcos V. Puydinger dos Santos,
• Silke Christiansen and
• Katja Höflich

Beilstein J. Nanotechnol. 2018, 9, 1220–1227, doi:10.3762/bjnano.9.113

• . Optical transmission/reflection measurements of deposited pads showed a dielectric behavior of the material in the optical spectral range. The general behavior of the permittivity could be described by applying the Maxwell–Garnett mixing model to amorphous carbon and copper. The dielectric function

• investigated concerning their morphology, composition and electrical properties. Transmission and reflection spectra of planar deposits of various heights served as input for the retrieval of the complex permittivity of the copper-containing material. The obtained values were used to numerically model the

• function of the resulting material since the permittivity of a metal depends on the oxidation state. To survey the oxidation state in detail, cross-sections of FEBID deposits were investigated by transmission electron microscopy (TEM). Figure 2c and Figure 2d show the inner FEBID structure of the copper

Theoretical study of strain-dependent optical absorption in a doped self-assembled InAs/InGaAs/GaAs/AlGaAs quantum dot

• Tarek A. Ameen,
• Hesameddin Ilatikhameneh,
• Archana Tankasala,
• Yuling Hsueh,
• James Charles,
• Jim Fonseca,
• Michael Povolotskyi,
• Jun Oh Kim,
• Sanjay Krishna,
• Monica S. Allen,
• Jeffery W. Allen,
• Rajib Rahman and
• Gerhard Klimeck

Beilstein J. Nanotechnol. 2018, 9, 1075–1084, doi:10.3762/bjnano.9.99

• initial and final states, ń is the refractive index of the material, c is the speed of light in free space, ε0 is the free space permittivity, is the polarization of the incident light, and is the first-order dipole moment that is given by , where q is the electron charge. For transitions between bound

Nanoscale mapping of dielectric properties based on surface adhesion force measurements

• Ying Wang,
• Yue Shen,
• Xingya Wang,
• Zhiwei Shen,
• Bin Li,
• Jun Hu and
• Yi Zhang

Beilstein J. Nanotechnol. 2018, 9, 900–906, doi:10.3762/bjnano.9.84

• liquid interfacial tension, θ0 is the contact angle at zero external voltage, and d, εr and ε0 are the thickness, relative permittivity of the dielectric layer, and the absolute dielectric permittivity of vacuum, respectively. Hence, the adhesion force between the AFM tip and the sample is affected by

Effect of annealing treatments on CeO₂ grown on TiN and Si substrates by atomic layer deposition

• Silvia Vangelista,
• Rossella Piagge,
• Satu Ek and
• Alessio Lamperti

Beilstein J. Nanotechnol. 2018, 9, 890–899, doi:10.3762/bjnano.9.83

• permittivity (κ) of 23–24 [5]. In all the cases, the valence of the Ce ions is fundamental, since it determines some of the material specific ability, such as the oxygen storage. More generally, the structure of cerium oxide is essential in defining its specific capabilities [6]. At the thermodynamic