Andreev spectrum and supercurrents in nanowire-based SNS junctions containing Majorana bound states

• Jorge Cayao,
• Annica M. Black-Schaffer,
• Elsa Prada and
• Ramón Aguado

Beilstein J. Nanotechnol. 2018, 9, 1339–1357, doi:10.3762/bjnano.9.127

• exhibits a clear sawtooth profile at a phase difference of π when the energy splitting is negligible, signalling a strong dependence of current–phase curves on the length of the superconducting regions. Effects of temperature, scalar disorder and reduction of normal transmission on supercurrents are also

• , therefore signalling the presence of weakly overlapping MBSs. We find that while this sawtooth profile is robust against variations in the normal transmission and scalar disorder, it smooths out when temperature effects are included, making it a fragile, yet useful, signature of MBSs. We identify that in

• of the maximum supercurrent. In particular, well-localized MBSs are revealed in the sawtooth profile of I() at = π. In what follows we analyze the effect of temperature, variation of normal transmission and random disorder on the sawtooth profile at = π of the supercurrent. Temperature effects In

Induced smectic phase in binary mixtures of twist-bend nematogens

• Anamarija Knežević,
• Irena Dokli,
• Marin Sapunar,
• Suzana Šegota,
• Ute Baumeister and
• Andreja Lesac

Beilstein J. Nanotechnol. 2018, 9, 1297–1307, doi:10.3762/bjnano.9.122

• intercalated smectic phase was unravelled by combined spectroscopic and computational methods and can be traced to conformational disorder of the terminal chains. These results show the importance of understanding the phase behaviour of binary mixtures, not only in targeting a wide temperature range but also

• considered to be mostly trans-planar [44]. The increase in hydrocarbon chain conformational disorder has also been intensively studied by FTIR on phospholipid bilayers and is used for monitoring of lipid hydrocarbon chain melting phase transitions [39][45][46][47]. The temperature dependent IR spectra of

• accordance with the increase of the motional rate of the molecule [37][39][41]. Considering the chemical structure of both pure compounds, it is reasonable to assume that shifting of CH2 vibrations rises from conformational disorder of terminal chains present only in the structure of BB. In order to

Electrodeposition of reduced graphene oxide with chitosan based on the coordination deposition method

• Mingyang Liu,
• Yanjun Chen,
• Chaoran Qin,
• Zheng Zhang,
• Shuai Ma,
• Xiuru Cai,
• Xueqian Li and
• Yifeng Wang

Beilstein J. Nanotechnol. 2018, 9, 1200–1210, doi:10.3762/bjnano.9.111

• intensity ratio of the D to G-band can be employed to evaluate the structure disorder of carbon materials [30][31]. Thus, the Raman spectroscopy analysis of HACC-rGO suggests that there exist some structural defects in HACC-rGO. Particularly, the resulting HACC-rGO disperses well in aqueous solutions, and

Inverse proximity effect in semiconductor Majorana nanowires

• Alexander A. Kopasov,
• Ivan M. Khaymovich and
• Alexander S. Mel'nikov

Beilstein J. Nanotechnol. 2018, 9, 1184–1193, doi:10.3762/bjnano.9.109

• disorder at the interface. Thus, the ensemble average of the tunneling amplitudes has the form: where is the length of the order of the atomic scale. The tunneling is also assumed to be independent of energy and spin and occurs locally in time and in space, i.e., from a point r on the superconducting

Thermoelectric current in topological insulator nanowires with impurities

• Sigurdur I. Erlingsson,
• Jens H. Bardarson and
• Andrei Manolescu

Beilstein J. Nanotechnol. 2018, 9, 1156–1161, doi:10.3762/bjnano.9.107

• = 4.0 T, for a nanowire of length L = 1000 nm. The disorder strength is set to W = 4.8 and the density of impurities is varied: ni = 3.0 nm−1, 6.0 nm−1 and 12 nm−1. For comparison, we consider two types of impurities: scalar impurities described by Equation 3 (red traces), and magnetic impurities

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

• electrons and holes. It is worth noting that the hole ground state has an s-orbital-like shape. QDs have a complicated band profile since multiple effects such as geometric confinement, strain and alloy disorder, can cause major changes in the band edges of the bulk material. It is important to know where

• to longer absorption wavelengths. In conclusion, the method presented here provides a way to incorporate the inhomogeneous environment of QDs in simulations by taking into account device geometry and quantum confinement, alloy disorder, electrostatics, many-particle interactions, and spatially

Synthesis and characterization of two new TiO₂-containing benzothiazole-based imine composites for organic device applications

• Anna Różycka,
• Agnieszka Iwan,
• Krzysztof Artur Bogdanowicz,
• Michal Filapek,
• Natalia Górska,
• Damian Pociecha,
• Marek Malinowski,
• Patryk Fryń,
• Agnieszka Hreniak,
• Jakub Rysz,
• Paweł Dąbczyński and
• Monika Marzec

Beilstein J. Nanotechnol. 2018, 9, 721–739, doi:10.3762/bjnano.9.67

• band positions shift by about 5 cm−1 for νas(CH2) and 6 cm−1 for νs(CH2) modes above the isotropisation temperature. This shows the increase of conformational disorder and mobility in hydrocarbon chains as liquid phase is formed. Figure 3b illustrates the evolution of the IR spectrum of SP2 at

The effect of atmospheric doping on pressure-dependent Raman scattering in supported graphene

• Egor A. Kolesov,
• Mikhail S. Tivanov,
• Olga V. Korolik,
• Olesya O. Kapitanova,
• Xiao Fu,
• Hak Dong Cho,
• Tae Won Kang and
• Gennady N Panin

Beilstein J. Nanotechnol. 2018, 9, 704–710, doi:10.3762/bjnano.9.65

• pronounced after the transfer. For doped graphene (1.11% of nitrogen from XPS data), the D band intensity increases compared to pristine graphene, the second disorder-induced peak (the D’ band) also becomes evident, the G peak position is upshifted by ≈3 cm−1, while the 2D peak is about normal, naturally

Tuning adhesion forces between functionalized gold colloidal nanoparticles and silicon AFM tips: role of ligands and capillary forces

• Sven Oras,
• Sergei Vlassov,
• Marta Berholts,
• Rünno Lõhmus and
• Karine Mougin

Beilstein J. Nanotechnol. 2018, 9, 660–670, doi:10.3762/bjnano.9.61

• ligands chain length, tail group and the packing order (disorder) of the molecular coating makes functionalized NPs an attractive model systems for studying the nature of interactions, and particularly adhesion at the nano and molecular level. The prospect of modifying the chain length of the ligands

• ) self-assemble on a surface with rather a poor packing [2]. This kind of structuration leads to low density of molecules on the surface. As a result, short chains have more structural disorder and defects that promote energy dissipation through rotational and vibrational excitation modes [30]. These

Single-step process to improve the mechanical properties of carbon nanotube yarn

• Maria Cecilia Evora,
• Xinyi Lu,
• Nitilaksha Hiremath,
• Nam-Goo Kang,
• Kunlun Hong,
• Roberto Uribe,
• Gajanan Bhat and
• Jimmy Mays

Beilstein J. Nanotechnol. 2018, 9, 545–554, doi:10.3762/bjnano.9.52

• −1 and 2000 cm−1. The peaks around 1580 cm−1 and 1350 cm−1 correspond to the G band (C=C in-plane stretching mode) and D band (disorder), respectively. The D band originates from hybridized vibrational mode associated with graphene edges. It indicates the presence of some disorder in the graphene

• structure. The degree of disorder in sp2-hybridized carbon materials is given by the intensity ratio between the D band and the G band (ID/IG) [36]. This ratio is thus useful to investigate the functionalization process. The broad band around 500 cm−1 observed in the spectra of the untreated samples may be

Revealing the interference effect of Majorana fermions in a topological Josephson junction

• Jie Liu,
• Tiantian Yu and
• Juntao Song

Beilstein J. Nanotechnol. 2018, 9, 520–529, doi:10.3762/bjnano.9.50

• period of 4π and the interference pattern is correlated with the parity. Furthermore, this relation is still valid in the presence of moderate disorder. Figure 1b and Figure 1c are calculated for the Gaussian disorder of w = 0.06t. We can see that the relation still holds. Interestingly, when the two

• -correlated interference effect for the trivial case. Third, the maximum (minimum) value of the DOS is at = (2n + 1)π for the trivial case and at 2nπ for the nontrivial case. In Figure 1d, we show the energy spectrum as a function of the flux under strong disorder, w = 0.13t with μ = −2t + 5.7Δ. It is

• typical that the two trivial Andreev bound states are accidentally in contact with each other for the strong disorder. From Figure 1b and Figure 1d, we can see that the energy spectra are very similar between the trivial case without the MFs and the nontrivial case with the MFs. In this situation, it is

Ultralight super-hydrophobic carbon aerogels based on cellulose nanofibers/poly(vinyl alcohol)/graphene oxide (CNFs/PVA/GO) for highly effective oil–water separation

• Zhaoyang Xu,
• Huan Zhou,
• Sicong Tan,
• Xiangdong Jiang,
• Weibing Wu,
• Jiangtao Shi and
• Peng Chen

Beilstein J. Nanotechnol. 2018, 9, 508–519, doi:10.3762/bjnano.9.49

• , respectively, showing the tangential G-band at 1587 cm−1 and the disorder-induced D-band at 1347 cm−1 [31]. As is well-known, the G-band corresponds to the tangential vibration of the carbon atoms, while the D-band corresponds to unordered carbon or defective graphitic structures in a Raman spectrum for carbon

• spectrum. After the carbonization treatment (Figure 4f), all characteristic bands of the carbon aerogel are tangential G-bands and the disorder-induced D-band, which are in agreement with the SEM and FTIR results. To further confirm the reduction degree of the GO during the carbonization treatment, X-ray

Engineering of oriented carbon nanotubes in composite materials

• Razieh Beigmoradi,
• Abdolreza Samimi and
• Davod Mohebbi-Kalhori

Beilstein J. Nanotechnol. 2018, 9, 415–435, doi:10.3762/bjnano.9.41

• mode (G-band), disorder-induced mode (D-band), and other Raman features, determining the physical properties of the material. The G-band intensity as a function of the angle of polarization for individual CNTs can be related to their arrangement so that the G-band intensity of well-aligned CNT bulk

Co-reductive fabrication of carbon nanodots with high quantum yield for bioimaging of bacteria

• Jiajun Wang,
• Xia Liu,
• Gesmi Milcovich,
• Tzu-Yu Chen,
• Edel Durack,
• Sarah Mallen,
• Yongming Ruan,
• Xuexiang Weng and
• Sarah P. Hudson

Beilstein J. Nanotechnol. 2018, 9, 137–145, doi:10.3762/bjnano.9.16

• carbon can be clearly detected for Sa, Sb and Se. The D-band, located at 1387 cm−1, correlates to the disorder or defects in the graphitized structure (sp3-hybridized carbon), while the G-band (1540 cm−1) is assigned to the E2g mode of graphite and corresponds to the vibration of sp2-bonded carbon atoms

• in a two-dimensional hexagonal [35]. The intensity ratio of the D- to G-band (ID/IG) is a measure of the extent of disorder, and the ratio of sp3/sp2 carbon. Sa has an ID/IG ratio of 0.86, and a ratio of 1 in both Sb and Se was found. The lower ID/IG value of Sb suggests that Sb is composed of more

Dry adhesives from carbon nanofibers grown in an open ethanol flame

• Christian Lutz,
• Julia Syurik,
• C. N. Shyam Kumar,
• Christian Kübel,
• Michael Bruns and
• Hendrik Hölscher

Beilstein J. Nanotechnol. 2017, 8, 2719–2728, doi:10.3762/bjnano.8.271

• materials, indicating defects in sp2-hybridized carbon. The G-band indicates stretching of the C–C bonds, characteristic for CNTs, CNFs, or other graphitic materials [40]. The D/G ratio is a measure of disorder in nanofibers. The randomly oriented CNFs show a significantly higher value than the oriented

One-step chemical vapor deposition synthesis and supercapacitor performance of nitrogen-doped porous carbon–carbon nanotube hybrids

• Egor V. Lobiak,
• Lyubov G. Bulusheva,
• Ekaterina O. Fedorovskaya,
• Yury V. Shubin,
• Pavel E. Plyusnin,
• Pierre Lonchambon,
• Boris V. Senkovskiy,
• Zinfer R. Ismagilov,
• Emmanuel Flahaut and
• Alexander V. Okotrub

Beilstein J. Nanotechnol. 2017, 8, 2669–2679, doi:10.3762/bjnano.8.267

•  6a). The ratio of intensities of these bands is often used for the estimation of the disorder in graphitic materials [40]. The calculated ID/IG value is equal to 1.27, 1.30, and 1.54 for the materials synthesized using Fe/Mo, Co/Mo, and Ni/Mo (Figure 6b). An increase in the ID/IG ratio correlates

Patterning of supported gold monolayers via chemical lift-off lithography

• Liane S. Slaughter,
• Kevin M. Cheung,
• Sami Kaappa,
• Huan H. Cao,
• Qing Yang,
• Thomas D. Young,
• Andrew C. Serino,
• Sami Malola,
• Jana M. Olson,
• Stephan Link,
• Hannu Häkkinen,
• Anne M. Andrews and
• Paul S. Weiss

Beilstein J. Nanotechnol. 2017, 8, 2648–2661, doi:10.3762/bjnano.8.265

• accelerating voltage, sample height, and vapor pressure were adjusted so that patterns could be discerned. The level of contrast in VP-SEM also depends on the nature of the alkanethiol molecules and SAM disorder (e.g., the orientation and conformation of the molecules in the SAM) [5]. The Au–mercaptoundecanol

Strategy to discover full-length amyloid-beta peptide ligands using high-efficiency microarray technology

• Clelia Galati,
• Natalia Spinella,
• Lucio Renna,
• Danilo Milardi,
• Francesco Attanasio,
• Michele Francesco Maria Sciacca and
• Corrado Bongiorno

Beilstein J. Nanotechnol. 2017, 8, 2446–2453, doi:10.3762/bjnano.8.243

• high efficacy in the treatment of cognitive/memory disorder [32]: nootropic, neurotrophic, neuroprotective and anti-inflammatory effects, a high affinity for copper(II) ions, and a protective ability against metal-induced cell toxicity have been observed [33][34][35][36]. Hence, the role of Semax in

Coexistence of strongly buckled germanene phases on Al(111)

• Weimin Wang and
• Roger I. G. Uhrberg

Beilstein J. Nanotechnol. 2017, 8, 1946–1951, doi:10.3762/bjnano.8.195

• corresponding to a (3×3) periodicity with respect to Al(111). An optimized model of (2×2) germanene on a (3×3) Al unit cell was presented. Two Ge atoms were located on top of Al atoms 1.21–1.23 Å higher than the other Ge atoms. Ge deposition at temperatures below the “magic” range was reported to show disorder

Spin-dependent transport and functional design in organic ferromagnetic devices

• Guichao Hu,
• Shijie Xie,
• Chuankui Wang and
• Carsten Timm

Beilstein J. Nanotechnol. 2017, 8, 1919–1931, doi:10.3762/bjnano.8.192

• . Another aspect worth studying is the role of disorder, which is generically important in one-dimensional systems [65]. Finally, a simple spin-independent interfacial coupling between the OFs and the electrodes is considered here. In actual devices, orbital hybridization may happen between the interacting

Optical techniques for cervical neoplasia detection

• Tatiana Novikova

Beilstein J. Nanotechnol. 2017, 8, 1844–1862, doi:10.3762/bjnano.8.186

• characterized by loss of layered tissue architecture and an increase in tissue microstructural disorder in OCT images (Figure 12 b,c). The stromal layer demonstrates columnar proliferation towards the surface of tissue in the OCT image of a CIN 3 lesion (Figure 12b). The invasive carcinoma manifests itself in

Process-specific mechanisms of vertically oriented graphene growth in plasmas

• Subrata Ghosh,
• Shyamal R. Polaki,
• Niranjan Kumar,
• Sankarakumar Amirthapandian,
• Mohamed Kamruddin and
• Kostya (Ken) Ostrikov

Beilstein J. Nanotechnol. 2017, 8, 1658–1670, doi:10.3762/bjnano.8.166

• ][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50]. The role of gas composition, deposition time and nature of substrate on the growth of VGNs has been discussed [24][27][47]. The first two parameters underpin the two competing disorder-related mechanisms. These mechanisms

• spectra exhibit D + D″ (ca. 2450 cm−1), G′ (ca. 2705 cm−1), D + D′ (ca. 2948 cm−1) and 2D′ (ca. 3244 cm−1) peaks. The defect-related peaks (D, D′, D″ and the overtones) are attributed to high edge density, structural defects and disorder such as vacancies and strained hexagonal/non-hexagonal (pentagon or

• properties in terms of defects and disorder. In backscattering geometry, Raman spectroscopic data were recorded in the frequency region of 1000–3500 cm−1 for 30 s accumulation time using a 514 nm laser and 100× objective lens. The wetting properties of the films were measured by the sessile drop method with

Spin-chemistry concepts for spintronics scientists

• Konstantin L. Ivanov,
• Alexander Wagenpfahl,
• Carsten Deibel and
• Jörg Matysik

Beilstein J. Nanotechnol. 2017, 8, 1427–1445, doi:10.3762/bjnano.8.143

• carriers can be extracted to yield the photocurrent. The role of the spin in several loss mechanisms [30][36][37], which reduce the power conversion efficiency, is only partly understood. For instance, if the delocalization of charge carriers in the CTS is limited, for example, by energetic disorder, CTS

• disorder [38]. Two optimization strategies for improving the power conversion efficiency based on spin processes are singlet fission and triplet–triplet annihilation (TTA). Singlet fission is the spin allowed conversion of one spin singlet exciton to two spin triplet excitons, which can occur with high

Comprehensive Raman study of epitaxial silicene-related phases on Ag(111)

• Dmytro Solonenko,
• Ovidiu D. Gordan,
• Guy Le Lay,
• Dietrich R. T. Zahn and
• Patrick Vogt

Beilstein J. Nanotechnol. 2017, 8, 1357–1365, doi:10.3762/bjnano.8.137

• [23]. Based on these results, the spectral signatures of silicene-related superstructures are established. Our results reveal a fundamental difference among these superstructures, related to the ratio of structural order and disorder. Furthermore, the in situ Raman results allow the phase diagram to

• -like surface pattern [6][16]. This pattern originates from locally ordered areas that are surrounded by distorted or disordered zones. The ordered areas appear brighter in filled-states STM images, thus mimicking a Moiré pattern. Because of the inherent intrinsic disorder (ID) it is not reasonable to

• decrease of all modes observed at lower deposition temperatures with the exception of the mode at 155 cm−1, also present in this growth regime. Its energy and line shape indicate the disorder-related nature of this Raman band, particularly evident in the case of the “” structure, known to be mostly

Ultrasmall magnetic field-effect and sign reversal in transistors based on donor/acceptor systems

• Thomas Reichert and
• Tobat P. I. Saragi

Beilstein J. Nanotechnol. 2017, 8, 1104–1114, doi:10.3762/bjnano.8.112

• the framework of the bipolaron model. Bipolarons can be stabilized by the presence of counter charges [33][34][35]. Furthermore, the coulomb repulsive interaction occurring in the formation of bipolarons species can be compensated by a correspondingly high energetic disorder of the thin films [11][22

• ][36][37][38]. Doping of amorphous organic films results in a broadening of the density of states and, thus, is increasing the energetic disorder [39][40]. Therefore, the high density of intrinsic charges in Spiro-TTB/HAT-CN compositions as well as the broadened density of states leads to an increased

• , negative magnetoresistance is obtained. In the context of the bipolaron model, the magnetoresistive behaviour of Spiro-TTB/HAT-CN compositions can be discussed as follows: The doping process between Spiro-TTB and HAT-CN in thin films generates intrinsic counter charges and increases the energetic disorder