Silver-based SERS substrates fabricated using a 3D printed microfluidic device

• Phommachith Sonexai,
• Minh Van Nguyen,
• Bui The Huy and
• Yong-Ill Lee

Beilstein J. Nanotechnol. 2023, 14, 793–803, doi:10.3762/bjnano.14.65

• particles. The electric field is enhanced, and the Raman enhancement factor (EF) can reach 106 [6]. The induced amplification of the local field by plasmonic coupling occurs in nanometer-scale regions around the metal particles, the so-called electromagnetic “hot spots”. The chemical mechanism suggests the

• NPs. The SEM image of PS@Ag reveals the presence of nanoscale gaps between the Ag NPs, which act as hot spots with a high electric field intensity when exposed to laser irradiation (Figure S10c). To confirm the distribution of chemical elements on the SERS substrate, energy-dispersive X-ray

Current-induced mechanical torque in chiral molecular rotors

• Richard Korytár and
• Ferdinand Evers

Beilstein J. Nanotechnol. 2023, 14, 711–721, doi:10.3762/bjnano.14.57

• , so that each transmitted particle results in a shift δϑ. This operational principle is different than an earlier reported one [15], where an electric field was needed to continuously accelerate the electrons while they travel along a helical wire. When the rotation of the molecule is hindered by a

Investigations on the optical forces from three mainstream optical resonances in all-dielectric nanostructure arrays

• Guangdong Wang and
• Zhanghua Han

Beilstein J. Nanotechnol. 2023, 14, 674–682, doi:10.3762/bjnano.14.53

• center by a distance of d = 80 nm. Figure 2a presents the calculated transmission spectrum through this structure with the incident electric field polarized along the x-direction. It can be seen that a strong asymmetric optical resonance of the Fano-type is located around 1627 nm with a resonance Q

• force is dependent on the laser power, we should note that the light transmission spectra through the array is not if the nonlinear effect is ignored. So in the calculations of the transmission spectra and the on-resonance field distributions, the electric field magnitude of the incident plane wave is

• set as 1 [V/m]. Then the maximum electric field in Figures 2b, 3b, and 4b straightforwardly give the enhancement capability of the corresponding resonance. Moreover, two circular displacement currents with reverse rotational directions are formed in the x–y plane of the disk, indicating that two MD

Observation of multiple bulk bound states in the continuum modes in a photonic crystal cavity

• Rui Chen,
• Yi Zheng,
• Xingyu Huang,
• Qiaoling Lin,
• Chaochao Ye,
• Meng Xiong,
• Martijn Wubs,
• Yungui Ma,
• Minhao Pu and
• Sanshui Xiao

Beilstein J. Nanotechnol. 2023, 14, 544–551, doi:10.3762/bjnano.14.45

• . Such a periodic nanostructure array supports a BIC around 1.56 μm and has an infinite Q factor at the Г point, as shown in Figure 1b and Figure 1c, respectively. The electric field (E field) distribution of the eigenmode is shown in the inset of Figure 1b, and the white arrows indicate the in-plane E

• cell. (a) Schematic of a unit cell consisting of an AlGaAs nanoblock on a sapphire substrate. The side length and the height of the nanoblock are w and h, respectively. The period of the unit is p. (b) Band diagram related to the MD BIC mode. The electric field distribution for the mode at the Г point

Plasmonic nanotechnology for photothermal applications – an evaluation

• A. R. Indhu,
• L. Keerthana and
• Gnanaprakash Dharmalingam

Beilstein J. Nanotechnol. 2023, 14, 380–419, doi:10.3762/bjnano.14.33

• arrival at the expression for the LSPR frequency of a free electron cloud (as is typically assumed to be present in metals) starts with the relations between the dielectric displacement (D) of the electron gas in relation to the incident electric field (E) which it is [38] subjected to, given by wherein P

• is the polarization density. P can be arrived at by solving the equation of motion for a single electron as Hence the expression relating the dielectric displacement (D) and the external electric field can be obtained as where is the natural frequency of oscillation of the electron cloud. Comparing

• charges are arranged in the direction of electric field and negative charges opposite to the field, causing a polarisation. The wavelength-dependent electric field and dipole moment determine the dielectric property of the material and also the plasmon absorption (by affecting the polarizability, as was

Quercetin- and caffeic acid-functionalized chitosan-capped colloidal silver nanoparticles: one-pot synthesis, characterization, and anticancer and antibacterial activities

• Akif Hakan Kurt,
• Elif Berna Olutas,
• Fatma Avcioglu,
• Hamza Karakuş,
• Mehmet Ali Sungur,
• Cansu Kara Oztabag and
• Muhammet Yıldırım

Beilstein J. Nanotechnol. 2023, 14, 362–376, doi:10.3762/bjnano.14.31

• characteristic surface plasmon resonance (SPR) absorption peak, which is due to the collective oscillation of free surface electrons in resonance with the electric field component of incoming photons, is located at 404 nm. However, the evolution of the absorption curve exhibits changes after the introduction of

Quasi-guided modes resulting from the band folding effect in a photonic crystal slab for enhanced interactions of matters with free-space radiations

• Kaili Sun,
• Yangjian Cai,
• Uriel Levy and
• Zhanghua Han

Beilstein J. Nanotechnol. 2023, 14, 322–328, doi:10.3762/bjnano.14.27

• lead to an in-plane wave number-dependent resonance characteristic in both directions. Our numerical results demonstrate a local enhancement of the electric field magnitude by the order of 102, which is even more significant than those in most plasmonic structures. These quasi-guided modes with

• directions. This suggests the possibility of resonance tuning over an extended bandwidth by using the incident angle along two different directions as the tuning mechanism. More importantly, we further illustrate that these QGM resonances have a significantly enhanced local electric field, which is even

• formed and new sharp resonances will be superimposed onto the transmission spectrum. The setup of the incident beams with respect to the structure can be found in Figure 1a, where the electric field of Ey is used to excite the QGMs. A redshift of the resonance for a larger incident angle is observed for

Bismuth-based nanostructured photocatalysts for the remediation of antibiotics and organic dyes

• Akeem Adeyemi Oladipo and
• Faisal Suleiman Mustafa

Beilstein J. Nanotechnol. 2023, 14, 291–321, doi:10.3762/bjnano.14.26

• static electric field, which effectively aids in the separation and transfer of photogenerated carriers. Bulk Bi and Bi-based nanostructure morphologies can also be easily altered using a variety of synthesis techniques due to their unique electrical and optical properties, which are directly tied to the

• facile solvothermal technique. An intrinsic electric field is created at the interface as a result of the active migration of electrons from BiVO4 to NiSe2. This improves the separation efficiency of the photogenerated carriers, and the interaction at the interface lowers the bandgap of BiVO4, which in

A distributed active patch antenna model of a Josephson oscillator

• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2023, 14, 151–164, doi:10.3762/bjnano.14.16

• similar to a microstrip patch antenna. However, it is biased by a dc current distributed over the whole area of the junction. The oscillating electric field is generated internally via the ac-Josephson effect. In this work, I present a distributed, active patch antenna model of a Josephson oscillator. It

Batch preparation of nanofibers containing nanoparticles by an electrospinning device with multiple air inlets

• Dong Wei,
• Chengwei Ye,
• Adnan Ahmed and
• Lan Xu

Beilstein J. Nanotechnol. 2023, 14, 141–150, doi:10.3762/bjnano.14.15

• were higher than those prepared by other high-yield electrospinning devices. Keywords: batch preparation; electric field simulation; electrospinning device; functional nanofibers; nanoparticles; Introduction In recent years, due to the characteristics of high specific surface area, good electrical

• 100 nanofibers from ten SEM images of each sample. Simultaneously, the element distribution on the sample surface was characterized by a desktop SEM (TM3030, Hitachi LTD.). Electric field simulation Maxwell 3D was used to simulate the electric field distribution of EMAI under different voltages (40

• , the edge of the groove, and the air inlets. This was because the edge part would produce higher electric field intensity due to the tip effect, while the air inlets would produce more jets due to the auxiliary effect of air flow. When the air flow rate was 150 m3/h (Figure 2a), because of the

Characterisation of a micrometer-scale active plasmonic element by means of complementary computational and experimental methods

• Ciarán Barron,
• Giulia Di Fazio,
• Samuel Kenny,
• Silas O’Toole,
• Robin O’Reilly and
• Dominic Zerulla

Beilstein J. Nanotechnol. 2023, 14, 110–122, doi:10.3762/bjnano.14.12

• polaritons (SPPs) are mixed states of photons and electron density waves propagating along the interface between a conductor and a dielectric. As a result of this phenomenon, an electric field strongly confined in the z-direction is produced at the interface. As direct excitation of a smooth metallic surface

• electric field. This method provides access to the modulation of the electric field induced by varying Joule heating. Second, the spatially resolved thermal distribution of the active plasmonic element and the surrounding environment was measured through the use of SJEM. This information is required to

• fully model the spatial distribution of the induced electric field changes. While this investigation focused on the behaviour of a single active plasmonic element, the combination of high localisation and the ability to modulate individual plasmonic elements at unique frequencies enables the design of

Solvent-induced assembly of mono- and divalent silica nanoparticles

• Bin Liu,
• Etienne Duguet and
• Serge Ravaine

Beilstein J. Nanotechnol. 2023, 14, 52–60, doi:10.3762/bjnano.14.6

• by liquid bridging [23], and into a series of structures under an AC electric field [24]. The linear self-assembly of patchy gold nanorods tethered with hydrophobic polymer chains at both ends can be triggered by solvophobic attractions induced by a change in solvent quality [25]. By using post

Utilizing the surface potential of a solid electrolyte region as the potential reference in Kelvin probe force microscopy

• Nobuyuki Ishida

Beilstein J. Nanotechnol. 2022, 13, 1558–1563, doi:10.3762/bjnano.13.129

• changes when a DC voltage is applied between the electrodes in a simple electrochemical cell, as shown in Figure 1a. After applying the DC voltage for some time, the electric field in the solid electrolyte becomes shielded by the formation of a Li-depletion layer on the positive electrode side and a Li

• toward the negatively biased electrode, resulting in an ionic current flow. The ion current decays with time and, in principle, becomes zero when the electric field in the solid electrolyte is shielded by the accumulation and depletion of Li ions. Before starting each KPFM measurement, we waited 2–4 min

• this subtraction are shown in Figure 5a. In all the data, a voltage drop occurs at the Au electrode–solid electrolyte interfaces, and the potential change in the solid electrolyte region is constant. These results are direct experimental evidence that the electric field in the solid electrolyte was

Induced electric conductivity in organic polymers

• Konstantin Y. Arutyunov,
• Anatoli S. Gurski,
• Vladimir V. Artemov,
• Alexander L. Vasiliev,
• Azat R. Yusupov,
• Danfis D. Karamov and
• Alexei N. Lachinov

Beilstein J. Nanotechnol. 2022, 13, 1551–1557, doi:10.3762/bjnano.13.128

• , Ufa, Russia Institute of Molecule and Crystal Physics UFRC RAS, 450054, Ufa, Russia 10.3762/bjnano.13.128 Abstract Poly(diphenylene phthalide) (PDP) belongs to the class of carbocyclic organic electroactive polymers, which exhibits electric conductive properties when an external electric field and/or

• system. Relatively recently it was found that finite electric current can pass also through non-conjugated polymers. In the ground state they are wide-band dielectrics, but can exhibit high electric conductivity under the influence of such external parameters as mechanical stress and/or electric field [1

• methods [8][9]. Quantum chemical studies of PDP [10] have shown that its molecular structure is unstable with regard to interaction with an excess (thermal) electron and can result in a transition to a metastable state. However, in that state, e.g. induced by external electric field, the system is

Recent trends in Bi-based nanomaterials: challenges, fabrication, enhancement techniques, and environmental applications

• Vishal Dutta,
• Ankush Chauhan,
• Ritesh Verma,
• C. Gopalkrishnan and
• Van-Huy Nguyen

Beilstein J. Nanotechnol. 2022, 13, 1316–1336, doi:10.3762/bjnano.13.109

• electric field (IEF) between the layers. This electric field allows photogenerated charge carriers to be separated and moved effectively [17][18][19][20][21]. A range of visible-light-active Bi-based photocatalysts has lately raised curiosity among semiconductor photocatalysts. Bi3+ has a higher stability

• migration [95][96]. Photoinduced holes in n-type semiconductors are transported to p-type semiconductors by an electric field at the interface, whereas photoinduced electrons from p-type semiconductors are transported to n-type semiconductors (Figure 5b). Using simple and cost-effective experimental

• near the interface, which leads to an electric field. Also, the Fermi level of Bi2O3 goes down, while the level of Bi2S3 goes up. Along the Fermi level, the energy bands of both Bi2O3 and Bi2S3 are moving simultaneously in a downward and an upward direction. An equilibrium state, in which the Fermi

Studies of probe tip materials by atomic force microscopy: a review

• Ke Xu and
• Yuzhe Liu

Beilstein J. Nanotechnol. 2022, 13, 1256–1267, doi:10.3762/bjnano.13.104

• electric field. The nanotube tips produced by this method have strong adhesion and mechanical stability. Since the above methods require scanning electron microscopy (SEM) monitoring throughout the transfer process, the process is relatively time-consuming. Hafner et al. [40] proposed a new method to

• generates a high-density network of CNTs on the sidewalls of the cone tip to help anchor the carbon nanotubes protruding from the tip. With the aim of simplicity in design and method of operation, the growth method does not use plasma or electric field as an enhancing factor to obtain effective tips, nor

Application of nanoarchitectonics in moist-electric generation

• Jia-Cheng Feng and
• Hong Xia

Beilstein J. Nanotechnol. 2022, 13, 1185–1200, doi:10.3762/bjnano.13.99

• in practical applications and provide green energy for more electronic devices. (a) The water flow is driven by an external electric field in the “motor” part, so the water molecules gain kinetic energy, and then an electromotive force is generated in the "Generator" part. (b) A scanning electron

Analytical and numerical design of a hybrid Fabry–Perot plano-concave microcavity for hexagonal boron nitride

• Felipe Ortiz-Huerta and
• Karina Garay-Palmett

Beilstein J. Nanotechnol. 2022, 13, 1030–1037, doi:10.3762/bjnano.13.90

• analysis is performed, although diffraction losses have to be considered for an accurate description of the experimental limits of stability [21]. In the unstable regime (R2 < L2) extensive work has also been done [22][23]. Electric field distribution and resonant modes of the plano-concave microcavity A

• λ0/4n thickness layer of hBN (n = 1.72) was positioned on top of a 15-pair layer DBR with tantalum oxide (Ta2O5) and silicon oxide (SiO2) as the high- and low-index layers, respectively, on a (HL)15 configuration to ensure an electric field antinode at the surface of the hBN layer, making the hBN

• + DBR system a L(HL)15 dielectric stack. A transfer matrix model [24] was used to calculate the electric field distribution inside the hBN + DBR system (Figure 6). The full transfer matrix S of our microcavity is defined as: where L and I represent the transfer and interface matrix, respectively, of the

Numerical study on all-optical modulation characteristics of quantum cascade lasers

• Biao Wei,
• Haijun Zhou,
• Guangxiang Li and
• Bin Tang

Beilstein J. Nanotechnol. 2022, 13, 1011–1019, doi:10.3762/bjnano.13.88

• active region of the QCL. The injected laser will then not be able to excite the electrons in the valence band to the laser subband of the conduction band, and the transition of electrons in the conduction band will be affected by the electric field. Therefore, we can allocate all the photoexcited

Effects of focused electron beam irradiation parameters on direct nanostructure formation on Ag surfaces

• Jānis Sniķeris,
• Vjačeslavs Gerbreders,
• Andrejs Bulanovs and
• Ēriks Sļedevskis

Beilstein J. Nanotechnol. 2022, 13, 1004–1010, doi:10.3762/bjnano.13.87

• . The first would be the height increase of the nanostructure when the EB diameter was reduced from 15 to 10 nm, while maintaining the same beam current. This observation supports the theory described in our previous work [30] regarding the movement of positive metal ions within the electric field

• formed around a negatively charged EB, promoting nanostructure formation on metal surfaces. A smaller beam diameter would imply a higher current density and a stronger local electric field, resulting in a larger attractive force on the metal ions. The second observation is the existence of a curve peak

• around a beam current value of 40 pA. The shape of the curve under 40 pA can be rather easily explained by the beam energy and current density. A higher beam current generally means that the electric field around the beam focus is stronger and that the beam thus supplies more energy to the surface for

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

• thermal drift between darkness and illumination. In the case of semiconductors, an electric field is screened on the scale of the Debye length LD [3], where kB is the Boltzmann constant, T is the temperature, ε0 is the vacuum permittivity, εr is the relative permittivity of the semiconductor, e is the

• intrinsic electric field [57][58][59]; however, this is beyond the scope of this paper. We note that the time scale of SPV measured with AC-KPFM is determined by the modulation frequency of the laser power and is faster (microseconds to milliseconds) than that in the case of classical KPFM (seconds to hours

Tunable high-quality-factor absorption in a graphene monolayer based on quasi-bound states in the continuum

• Jun Wu,
• Yasong Sun,
• Feng Wu,
• Biyuan Wu and
• Xiaohu Wu

Beilstein J. Nanotechnol. 2022, 13, 675–681, doi:10.3762/bjnano.13.59

• normal incidence owing to the subwavelength unit cell of this structure. Therefore, the radiation mode will be confined in the dielectric grating, which results in large electric field intensity enhancement and concentration inside the grating, as presented in Figure 3d. For a nonmagnetic dispersive

• medium, the time-averaged power loss density is described by [59]: dPloss/dV = 1/2ε0ω·Im (ε(ω))|E|2, where Im(ε) denotes the imaginary part of relative permittivity and E is the electric field. Thus, the strong electric intensity enhancement inside the dielectric grating will boost light absorption in

Revealing local structural properties of an atomically thin MoSe₂ surface using optical microscopy

• Lin Pan,
• Peng Miao,
• Anke Horneber,
• Alfred J. Meixner,
• Pierre-Michel Adam and
• Dai Zhang

Beilstein J. Nanotechnol. 2022, 13, 572–581, doi:10.3762/bjnano.13.49

• and microscopy are used to reveal the structural irregularities of the MoSe2 flake. The Raman enhancement in the focus of an azimuthally polarized beam, which possesses exclusively an in-plane electric field component is stronger than the enhancement by a focused radially polarized beam, where the out

• -of-plane electric field component dominates. This phenomenon indicates that the face-on oriented CuPc molecules strongly interact with the MoSe2 flake via charge transfer and dipole–dipole interaction. Furthermore, the Raman scattering maps on the irregular MoSe2 surface show a distinct correlation

• at the center. The insets in Figure 1f and Figure 1h show the calculated intensity distribution of the electric field in the x–y plane in the focus of the radially and azimuthally polarized laser beam, respectively. The center of a focused radial polarization beam exhibits mainly a z-direction field

Zinc oxide nanostructures for fluorescence and Raman signal enhancement: a review

• Ioana Marica,
• Fran Nekvapil,
• Maria Ștefan,
• Cosmin Farcău and
• Alexandra Falamaș

Beilstein J. Nanotechnol. 2022, 13, 472–490, doi:10.3762/bjnano.13.40

• great interest and will be the focus of this review. The electromagnetic (EM) enhancement in surface-enhanced Raman scattering (SERS) appears due to the enhanced local electric field that is generated when localized surface plasmon resonances (LSPRs) are excited by light incident on noble metal

• Previous simulations have shown that the Ag NPs exhibit the greatest plasmonic activity in the excitation wavelength range of 400–520 nm and the greatest absorption and electric field energy enhancement at the size of 50–60 nm, while for AuNPs these ranges are 525–580 and 90–100 nm (and potentially bigger

Electrostatic pull-in application in flexible devices: A review

• Teng Cai,
• Yuming Fang,
• Yingli Fang,
• Ruozhou Li,
• Ying Yu and
• Mingyang Huang

Beilstein J. Nanotechnol. 2022, 13, 390–403, doi:10.3762/bjnano.13.32

• switch to open. After the circuit conduction or charge disappears, the switch is pulled in again. By analyzing the electric field in the comb structure, He et al. [91] showed that the side electrode would generate a repulsive force without introducing a current. Pallay et al. [85] proposed a sensor