New design of operational MEMS bridges for measurements of properties of FEBID-based nanostructures

• Bartosz Pruchnik,
• Krzysztof Kwoka,
• Ewelina Gacka,
• Dominik Badura,
• Piotr Kunicki,
• Andrzej Sierakowski,
• Paweł Janus,
• Tomasz Piasecki and
• Teodor Gotszalk

Beilstein J. Nanotechnol. 2024, 15, 1273–1282, doi:10.3762/bjnano.15.103

• apex by choosing appropriate dwell time and pitch for the deposition. The dimensions of the nanowire were 60 nm in diameter and 1.6 μm in length. The junction was tested by resistance measurements (Figure 8b). The measured resistance was 12 MΩ, giving a resistivity of approximately 2.1 Ω·cm, which is

Quantum-to-classical modeling of monolayer Ge₂Se₂ and its application in photovoltaic devices

• Anup Shrivastava,
• Shivani Saini,
• Dolly Kumari,
• Sanjai Singh and
• Jost Adam

Beilstein J. Nanotechnol. 2024, 15, 1153–1169, doi:10.3762/bjnano.15.94

• between active and transport layers The photovoltaic behavior of halide perovskites is significantly affected by the properties of the interfaces. This is because a majority of defects arises at the junction between two layers during the fabrication of the device, caused by mismatches in the lattice

Photocatalytic methane oxidation over a TiO₂/SiNWs p–n junction catalyst at room temperature

• Qui Thanh Hoai Ta,
• Luan Minh Nguyen,
• Ngoc Hoi Nguyen,
• Phan Khanh Thinh Nguyen and
• Dai Hai Nguyen

Beilstein J. Nanotechnol. 2024, 15, 1132–1141, doi:10.3762/bjnano.15.92

• recombination of charge carriers in semiconductors is a main drawback for photocatalytic oxidative coupling of methane (OCM) reactions. Herein, we propose a novel catalyst by developing a p–n junction titania–silicon nanowires (TiO2/SiNWs) heterostructure. The structure is fabricated by atomic layer deposition

• electrons for reactions [25][26][27]. However, the generated electron affinity of metal NPs is sometimes insufficient and cannot prevent recombination or maintain electrons for further reactions. As an advanced solution for catalysis modification, p–n junction photocatalysts with an intrinsic electric field

• tools is extremely essential and important [37][38][39]. Herein, we constructed a robust p–n junction catalyst by atomic layer deposition (ALD) of TiO2 thin films on a p-type SiNW substrate for enhancing the photocatalytic efficiency in CH4 oxidation. Pristine p-Si wafers have limited surface area and

Bolometric IR photoresponse based on a 3D micro-nano integrated CNT architecture

• Yasameen Al-Mafrachi,
• Sandeep Yadav,
• Sascha Preu,
• Jörg J. Schneider and
• Oktay Yilmazoglu

Beilstein J. Nanotechnol. 2024, 15, 1030–1040, doi:10.3762/bjnano.15.84

• thermistor region, can be fabricated in a single chemical vapor deposition process step. The thermistor resistance is mainly determined by the high junction resistances of the adjacent aligned CNTs. This configuration also provides low lateral thermal conductivity and a high temperature coefficient of

• applications [3]. The device resistance perpendicular to the CNT orientation is mainly determined by the high junction resistances of the neighboring aligned CNTs [4]. This configuration allows for high device resistance, low thermal conductivity, and high temperature coefficient of resistance, thus, enabling

• material. The electrical conductivity of a vertically aligned CNT structure is defined by the intrinsic conductivity along the CNTs and the tunneling at the CNT junctions. The vertical electrical conduction is based on long conduction paths along the CNTs and few junction contacts, while the lateral

Recent progress on field-effect transistor-based biosensors: device perspective

• Billel Smaani,
• Fares Nafa,
• Mohamed Salah Benlatrech,
• Ismahan Mahdi,
• Hamza Akroum,
• Mohamed walid Azizi,
• Khaled Harrar and
• Sayan Kanungo

Beilstein J. Nanotechnol. 2024, 15, 977–994, doi:10.3762/bjnano.15.80

• inner and outer gate cavity regions is set to 10 nm [63]. Therefore, the physical properties of the biosensor have been analyzed via source-channel junction electrostatics and thermionic emission. The effect of applying biasing conditions on the efficiency of the transduction is also investigated. It

• , forming a plasma layer of holes. An abrupt junction at the channel/source was created to facilitate the entry of biomolecules into the cavity. Thus, significant variations in electrostatic properties were observed due to the distinct characteristics of the biomolecules, leading to improved sensitivity

• presents the organization of PKD FET-based biosensor. This structure uses the double-gate architecture with III–V compound semiconductors at the channel and an N+-doped pocket at the junction between the source and channel regions. The drain and source regions are realized with GaSb material. HfO2 was used

Reduced subthreshold swing in a vertical tunnel FET using a low-work-function live metal strip and a low-k material at the drain

• Kalai Selvi Kanagarajan and
• Dhanalakshmi Krishnan Sadhasivan

Beilstein J. Nanotechnol. 2024, 15, 713–718, doi:10.3762/bjnano.15.59

• dielectric gate contains a molybdenum live strip, which raises the electron concentration at the source–channel junction because of its low work function. The rise in electron concentration creates an abrupt change in the source channel. Figure 3 presents the electric field of the VTFET with DLWLS + spacer

• DLWLS + spacer, 25 mV/dec for DLWLS, and 30 mV/dec for the design with only the spacer. The subthreshold swing of a TFET depends on the high-k gate dielectric and a thin body to assure that the gate field directly modulates the channel. Maximizing the derivative of the junction electric field on the

• gate–source voltage [4] is another method for reducing the subthreshold voltage swing. Veff is the tunnel–junction bias, ξ is the electric field, a, b are coefficients based on the junction's material characteristics and the device’s cross-sectional area: Comparison of VTFET with VTFET (DLWLS and

Superconducting spin valve effect in Co/Pb/Co heterostructures with insulating interlayers

• Andrey A. Kamashev,
• Nadir N. Garif’yanov,
• Aidar A. Validov,
• Vladislav Kataev,
• Alexander S. Osin,
• Yakov V. Fominov and
• Ilgiz A. Garifullin

Beilstein J. Nanotechnol. 2024, 15, 457–464, doi:10.3762/bjnano.15.41

• in a conventional tunneling junction”. While the theory [50] assumes a symmetric F1/S/F2 structure, our samples may actually be asymmetric from the point of view of the interface transparencies. The oxidation times of the two interfaces were different in our samples, and our fabrication procedure was

Unveiling the nature of atomic defects in graphene on a metal surface

• Karl Rothe,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2024, 15, 416–425, doi:10.3762/bjnano.15.37

• . Constant-height scanning tunneling spectroscopy (STS) of dI/dV was performed by sinusoidally modulating (5 mVrms, 725 Hz) the dc bias voltage and measuring the first harmonic of the ac current response of the tunneling junction with a lock-in amplifier. For AFM data acquisition, resonance frequency changes

• inversion is induced by the reduction of the tip–graphene separation. As will be shown below, the involved junction currents correspond to a separation that is still larger than, but close to, the point of maximum attractive force. Therefore, a tentative rationale to the observed contrast inversion is the

• increased tip–graphene hybridization compared to the far tunneling range, which may entail a modification of the graphene electronic structure or enhance the contribution of substrate states to the junction current [46]. The mounds and adjacent valleys of the moiré superstructure are characterized by

Controllable physicochemical properties of WO_x thin films grown under glancing angle

• Rupam Mandal,
• Aparajita Mandal,
• Alapan Dutta,
• Rengasamy Sivakumar,
• Sanjeev Kumar Srivastava and
• Tapobrata Som

Beilstein J. Nanotechnol. 2024, 15, 350–359, doi:10.3762/bjnano.15.31

• for the as-deposited and annealed NS-WOx/p-Si heterojunctions at three different applied voltages (V), viz. ±0.5, ±0.7, and ±1 V, where a higher value of RR indicates a stronger rectifying nature of a junction. As can be seen from Table 1, an increase in the film thickness minimizes the RR value of

• the junction, thereby leading to more symmetric I–V curves. Nevertheless, one can infer from the observed low values of RR (Table 1) that all the as-deposited NS-WOx/p-Si samples show a quasi-ohmic conduction behaviour, which implies that tunnelling may be responsible for the current transport. The

• -deposited films, compared to the annealed ones, indicating a quasi-ohmic nature of the junction. Increased rectification ratios are observed for thinner WOx films, which are insufficient to overcome the metal electrode-induced gap states at the interface leading to Fermi level pinning. Improved current

Josephson dynamics and Shapiro steps at high transmissions: current bias regime

• Artem V. Galaktionov and
• Andrei D. Zaikin

Beilstein J. Nanotechnol. 2024, 15, 51–56, doi:10.3762/bjnano.15.5

• junctions is the presence of coherent current oscillations with the fundamental frequency ωJ = 2 eV/ℏ, where V is the voltage applied to the junction and −e is the electron charge. Under the influence of external microwave radiation with frequency ω, current jumps appear on the junction I–V curve, which are

• modified by replacing V by its time average V→. Dissipation usually plays an important role in the case of current-biased superconducting nanojunctions. One possible way to account for dissipative currents is to employ the so-called resistively shunted junction (RSJ) model [1]. In the case of tunnel

• T → 0 can flow across the junction. The situation becomes entirely different provided one goes beyond the tunneling limit and considers highly transparent superconducting weak links in which case the charge transfer is essentially controlled by the mechanism of multiple Andreev reflection [2]. This

Measurements of dichroic bow-tie antenna arrays with integrated cold-electron bolometers using YBCO oscillators

• Leonid S. Revin,
• Dmitry A. Pimanov,
• Alexander V. Chiginev,
• Anton V. Blagodatkin,
• Viktor O. Zbrozhek,
• Andrey V. Samartsev,
• Anastasia N. Orlova,
• Dmitry V. Masterov,
• Alexey E. Parafin,
• Victoria Yu. Safonova,
• Anna V. Gordeeva,
• Andrey L. Pankratov,
• Leonid S. Kuzmin,
• Anatolie S. Sidorenko,
• Silvia Masi and
• Paolo de Bernardis

Beilstein J. Nanotechnol. 2024, 15, 26–36, doi:10.3762/bjnano.15.3

• measured with YBCO Josephson Junction oscillators show narrow peaks at 205 GHz for the 210 GHz array and at 225 GHz for the 240 GHz array; the separation of these two frequency bands is clearly visible. The noise equivalent power level at an operating point in the current bias mode is 5 × 10−16 W/√Hz

• . Keywords: cosmic microwave background; B mode; cold-electron bolometer; dichroic antenna array; dipole bow-tie antenna; Josephson junction; LSPE; Introduction The cosmic microwave background (CMB) radiation contains a lot of information about origin and evolution of our universe. The temperature and

• the order of a few micrometers, detector can be placed inside the antenna slot without additional microwave feed lines, forming a multi-absorber array [15][17][18]. Because of this feature, one can adjust the total resistance by forming series or parallel arrays of CEBs to match for either junction

A bifunctional superconducting cell as flux qubit and neuron

• Dmitrii S. Pashin,
• Pavel V. Pikunov,
• Marina V. Bastrakova,
• Andrey E. Schegolev,
• Nikolay V. Klenov and
• Igor I. Soloviev

Beilstein J. Nanotechnol. 2023, 14, 1116–1126, doi:10.3762/bjnano.14.92

• by the second term in Equation 1, wherein the effective coordinate is a phase of the Josephson junction, φ. The quantities Ec = and EJ = are the capacitive and the Josephson energy, respectively, determined by critical current Ic and the capacity C of the Josephson junction. A typical example of

• . The action time of the symmetric input flux to avoid Landau–Zener transitions is ∼100 ns for l = 2. The estimate was made with the characteristic parameters of a Josephson junction, that is, Ic = 50 nA and C = 6 fF. In contrast, it takes ∼30 ns for the transition from the ground state to the first

• ⟩ = bφin(t) − a⟨φ⟩ is the mean value of the current operator on the Josephson junction when the external flux changes relative to the mean phase of the contact ⟨φ⟩ = ⟨ψ(t)|φ|ψ(t)⟩. As shown in Figure 4a, the transfer characteristic of the parametron has a sigmoidal dependence. It is worth noting that this

Density functional theory study of Au-fcc/Ge and Au-hcp/Ge interfaces

• Olga Sikora,
• Małgorzata Sternik,
• Benedykt R. Jany,
• Franciszek Krok,
• Przemysław Piekarz and
• Andrzej M. Oleś

Beilstein J. Nanotechnol. 2023, 14, 1093–1105, doi:10.3762/bjnano.14.90

• . Our DFT calculations for the Au-fcc(011)/Ge(001) junction show how the presence of defects in the interface layer can help to stabilize the atomic pattern, consistent with microscopic images. Although the Au-hcp/Ge interface is characterized by a similar interface energy, it reveals large atomic

• optimized supercell shown in Figure 9d, the interface energy is slightly higher (0.395 J/m2) than that of the defect-free junction. We also tested another type of defects (Au vacancies). To construct the supercell, we first found the position of slabs with the smallest possible Au–Ge distances (two such

• -free optimized structure shown in Figure 9a. We can observe that the atomic pattern at the interface is well reproduced by our model. The interface seen in the experimental image is not as regular as the Au-fcc/Ge junction presented in Figure 8, and other types of defects may additionally stabilize

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

• (CPD). If one considers a simple junction formed by a metallic AFM tip and a metallic sample, the CPD originates from the tip–sample work function difference. More generally, the CPD stems from the existence of electric charges and/or dipoles in the system under consideration. As a result, the

Spatial mapping of photovoltage and light-induced displacement of on-chip coupled piezo/photodiodes by Kelvin probe force microscopy under modulated illumination

• Zeinab Eftekhari,
• Nasim Rezaei,
• Hidde Stokkel,
• Jian-Yao Zheng,
• Andrea Cerreta,
• Ilka Hermes,
• Minh Nguyen,
• Guus Rijnders and
• Rebecca Saive

Beilstein J. Nanotechnol. 2023, 14, 1059–1067, doi:10.3762/bjnano.14.87

• from the top reached the Si p–n junction and generated electron–hole pairs, building a potential difference across the junction. The generated photovoltage was applied to the piezoelectric capacitor through the photolithographically defined contacts and induced mechanical displacement in the

Cross-sectional Kelvin probe force microscopy on III–V epitaxial multilayer stacks: challenges and perspectives

• Mattia da Lisca,
• José Alvarez,
• James P. Connolly,
• Nicolas Vaissiere,
• Karim Mekhazni,
• Jean Decobert and
• Jean-Paul Kleider

Beilstein J. Nanotechnol. 2023, 14, 725–737, doi:10.3762/bjnano.14.59

• expected trend in a p-type layer with surface defects. However, in case of pn junctions, the SPV can also include the contribution of the open-circuit voltage (VOC) of the pn junction due to the splitting of the quasi-Fermi levels of electrons and holes and the related charge separation at the junction. In

• our case, because the n-type side of the junction (substrate) is grounded, we expect a positive SPV contribution from the VOC of the pn junction at the surface of the p layer outside the space charge region of the pn junction. Therefore, the SPV measured in the InP:Zn region should be a trade-off

• between the negative contribution due to the flattening of surface defect-related band bending and the positive contribution of VOC. As a consequence, the slightly negative SPV value of −95 mV measured in the InP:Zn region indicates a weaker contribution of the pn junction (VOC) compared to the change in

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

• unidirectional rotation in the STM setup requires a degree of symmetry breaking. There are two typical situations, that is, either the molecule by itself exhibits a handedness (chirality) or chirality is imposed by the geometry of the molecular junction [6][10]. The purpose of this article is to provide a

Overview of mechanism and consequences of endothelial leakiness caused by metal and polymeric nanoparticles

• Magdalena Lasak and
• Karol Ciepluch

Beilstein J. Nanotechnol. 2023, 14, 329–338, doi:10.3762/bjnano.14.28

• for the interaction with adherens junction proteins (e.g., VE-cadherin). The width of the endothelial gaps was ca. 22.5 nm [28]. Researchers observed that the interaction of the endothelium with NPs widens the existing gaps or induces new ones in the monolayer of vascular endothelial cells, thus

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

• applications, are addressed. Keywords: advanced oxidation processes; emerging contaminants; low-dimensional nanomaterials; pharmaceutical by-products; Schottky junction; Review Introduction Worldwide, water pollution is rising, endangering the economic potential and development objectives of severely

• were degraded by 94.8% and 81.1% after 1 h, respectively. Another strategy for overcoming constraints such as low charge migration and the unpredictable direction of charge diffusion is the construction of a Schottky junction. A Schottky junction can be created at the interface between the

• semiconductor and a noble metal with an appropriate work function. A unidirectional charge transfer is enabled by the Schottky potential barrier, increasing charge density and separation [72]. Shen et al. [166] created a Schottky junction by synthesising NiSe2 nanosheets on top of BiVO4 nanosheets using a

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

• Vladimir M. Krasnov Department of Physics, Stockholm University, AlbaNova University Center, SE-10691 Stockholm, Sweden 10.3762/bjnano.14.16 Abstract Optimization of Josephson oscillators requires a quantitative understanding of their microwave properties. A Josephson junction has a geometry

• 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

• takes into account the internal Josephson electrodynamics and allows for the determination of the effective input resistance, which couples the Josephson current to cavity modes in the transmission line formed by the junction. The model provides full characterization of Josephson oscillators and

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

• solution, forming a large potential difference resulting in the increase of electric field intensity [27]. Similarly, the electric field intensity dropped sharply and afterwards increased sharply at the junction of the groove and the spinneret edge (30 mm). At the edge of the porous spinneret (30–35 mm

Frontiers of nanoelectronics: intrinsic Josephson effect and prospects of superconducting spintronics

• Anatolie S. Sidorenko,
• Horst Hahn and
• Vladimir Krasnov

Beilstein J. Nanotechnol. 2023, 14, 79–82, doi:10.3762/bjnano.14.9

• [15][16]. - Detection of ultrahigh frequency radiation by new devices: Based on Josephson junctions with frequencies of 72–265 GHz using the Josephson grain boundary junction fabricated in YBaCuO films [17] and broad-band detectors based on YBaCuO Josephson junctions fabricated on ZrYO bicrystals with

• a very high responsivity at 77 K (up to 9 kV/W), low noise equivalent power (NEP) of 3 × 10−13 W/Hz(1/2), and with a wide power dynamic range equal to 1 × 106 [18]. Integrating an aluminum Josephson junction, with a size of a few micrometers, operating as a single photon counter in the microwave

• /ferromagnetic absorber with a temperature reduction of the electrons in the refrigerator junctions down to 25 mK in the idle regime without an optical power load [22]. - Implementation of Josephson junctions for the design of quantum computers by analyzing the dynamics of a single-junction superconducting

Observation of collective excitation of surface plasmon resonances in large Josephson junction arrays

• Roger Cattaneo,
• Mikhail A. Galin and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2022, 13, 1578–1588, doi:10.3762/bjnano.13.132

• as a common external resonator, facilitating long-range phase-locking of large junction arrays with sizes larger than the emitted wavelength. Keywords: cavity modes; Josephson junctions; synchronization mechanism; THz radiation; Introduction Terahertz sources of electromagnetic waves (EMWs) in the

• due to the presence of long-range stray fields [28]. Indirect coupling is caused by interaction of JJs with a common external resonator [7][8][29][30][31][32][33][34][35]. The resonator imprints the phase order onto the junction array and, thus, can synchronize JJs without direct interjunction

• . Each segment contains eight overlap-type JJs with the area 6 × 6 μm2. This can be seen from the close-up shown in the left panel of Figure 1a. The distance between nearby junction centers is 12 μm. A cross section of the junctions is sketched in the bottom-left panel of Figure 1c. The linear array

Coherent amplification of radiation from two phase-locked Josephson junction arrays

• Mikhail A. Galin,
• Vladimir M. Krasnov,
• Ilya A. Shereshevsky,
• Nadezhda K. Vdovicheva and
• Vladislav V. Kurin

Beilstein J. Nanotechnol. 2022, 13, 1445–1457, doi:10.3762/bjnano.13.119

• , but also improved synchronization of junctions inside each array. Our conclusion is supported by numerical modelling. Keywords: coherent radiation; Josephson junction arrays; numerical modelling; single-strip line; synchronization; Introduction A Josephson junction (JJ) has the unique ability to

• substrate with the thickness 0.38 mm. It contains three closely located straight strips with a separation of only 4 μm. Each strip has the length L = 5 mm and the width w = 14 μm and contains 332 JJs distributed uniformly along the strip. The junction area is 8 × 8 μm2. Contact electrodes are connected to

• significantly larger separation of 238 μm between the adjacent linear arrays. In total, it contains 17 similar lines with 380 JJs and a total length of L = 5.7 mm. The junction area is 6 × 6 μm2. Below, we will show data for the case when the rightmost “array-a” is biased with a variable dc current and the

Density of states in the presence of spin-dependent scattering in SF bilayers: a numerical and analytical approach

• Tairzhan Karabassov,
• Valeriia D. Pashkovskaia,
• Nikita A. Parkhomenko,
• Anastasia V. Guravova,
• Elena A. Kazakova,
• Boris G. Lvov,
• Alexander A. Golubov and
• Andrey S. Vasenko

Beilstein J. Nanotechnol. 2022, 13, 1418–1431, doi:10.3762/bjnano.13.117

• resistance. In the regime of a fully transparent junction, γB = 0, the proximity effect is the strongest, and the θ functions are continuous at the SF interface while γB ≫ 1 corresponds to the tunnel junction limit, that is, there is no mutual impact between superconducting layer S and ferromagnetic layer F

• mentioned in the previous section. In this paper we consider two cases of the junction transparency: (i) intermediate interface transparency (γB ≥ 1) and (ii) low interface transparency (γB ≫ 1). In both cases, we fix the thickness of the F layer to df = 0.5ξf. Focusing on these cases allows us to discuss

• features is the examination of the current–voltage characteristics. Utilizing the Werthamer expression for the quasiparticle current in tunneling junctions, we can calculate the I–V curves for an SFIFS junction. The current then reads Here, Nf1,2(E) is the density of states (DOS) in the corresponding