Ultrafast signatures of magnetic inhomogeneity in Pd_1−xFe_x (x ≤ 0.08) epitaxial thin films

• Andrey V. Petrov,
• Sergey I. Nikitin,
• Lenar R. Tagirov,
• Amir I. Gumarov,
• Igor V. Yanilkin and
• Roman V. Yusupov

Beilstein J. Nanotechnol. 2022, 13, 836–844, doi:10.3762/bjnano.13.74

• of order-of-magnitude estimation we define the spin-diffusion velocity vs as from which Modern band-structure calculations [48][49] show that more than 95% of the electron density of states at the Fermi energy comes from the itinerant 4d electrons. The Fermi velocity of 3d electrons in iron-group

Modeling a multiple-chain emeraldine gas sensor for NH₃ and NO₂ detection

• Hana Sustkova and
• Jan Voves

Beilstein J. Nanotechnol. 2022, 13, 721–729, doi:10.3762/bjnano.13.64

• to the other gases. The density of states, in this case, increases significantly above the Fermi level. Zhang et al. [11] already modeled sensors detecting single gas molecules using DFT. Also, in our previous work, computations with one emeraldine salt PANI chain and one ammonia molecule were

Experimental and theoretical study of field-dependent spin splitting at ferromagnetic insulator–superconductor interfaces

• Peter Machon,
• Michael J. Wolf,
• Detlef Beckmann and
• Wolfgang Belzig

Beilstein J. Nanotechnol. 2022, 13, 682–688, doi:10.3762/bjnano.13.60

• superconductivity [7][8], the triplet proximity effect [9][10][11], and implementations of superconducting switches and spin valves based on either the singlet or triplet proximity effect [12][13][14][15][16][17][18]. Furthermore, the spin-dependent density of states due to the proximity of a magnetic insulator is

• insulator [30][31], which has been extended meanwhile to insulating antiferromagnets [32]. Thus, one has the opportunity to quantitatively study the microscopic mechanisms that influence the superconducting density of states, in a way that they mainly shift and spin-split the peaks at the superconducting

• density of states of the superconducting film by tunnel spectroscopy. Results and Discussion Theory The setup of the underlying experiment is shown in Figure 1a. It consists (bottom-up) of an EuS substrate, a superconducting (Al) film, and a normal metal film that is separated from the superconductor by

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

• shown in Figure 3c, it induces an increase of the electron density of states. According to Fermi’s golden rule, the electron transition probability rate wlk can be expressed as: where the g(Ek) and denote the density of states and the matrix element for the LUMO–HOMO transition, respectively. Therefore

• , the electron transition probability can be increased by increasing the density of states, which plays a significant role in the ground-state charge-transfer process, further leading to an enhancement of electron–phonon coupling and, consequently, an increase of the Raman scattering intensity [39

Plasma modes in capacitively coupled superconducting nanowires

• Alex Latyshev,
• Andrew G. Semenov and
• Andrei D. Zaikin

Beilstein J. Nanotechnol. 2022, 13, 292–297, doi:10.3762/bjnano.13.24

• effects. One of them is the theoretically predicted [13][14] and experimentally observed [15][16] smearing of the square-root singularity in the density of states (DOS) near the superconducting gap accompanied by a non-vanishing tail in DOS at subgap energies. Mooij–Schön plasmons also mediate the

Theoretical understanding of electronic and mechanical properties of 1T′ transition metal dichalcogenide crystals

• Seyedeh Alieh Kazemi,
• Sadegh Imani Yengejeh,
• Vei Wang,
• William Wen and
• Yun Wang

Beilstein J. Nanotechnol. 2022, 13, 160–171, doi:10.3762/bjnano.13.11

• 0.79 and 0.80 Å, respectively. The radius of S2− is 1.84 Å, which is 0.14 Å smaller than that of Se2−. Electronic properties The electronic properties of 1T′ TMDs were first investigated through the analyses of their partial density of states (pDOS) of TM d states and X p states, as illustrated in

A photonic crystal material for the online detection of nonpolar hydrocarbon vapors

• Evgenii S. Bolshakov,
• Aleksander V. Ivanov,
• Andrei A. Kozlov,
• Anton S. Aksenov,
• Elena V. Isanbaeva,
• Sergei E. Kushnir,
• Aleksei D. Yapryntsev,
• Aleksander E. Baranchikov and
• Yury A. Zolotov

Beilstein J. Nanotechnol. 2022, 13, 127–136, doi:10.3762/bjnano.13.9

• removed, then it is an inverse opal structure [11][12][13]. A photonic bandgap (PBG) appears in colloidal crystals due to the periodic modulation of the refractive index. At the bandgap, selective reflection of light is observed, which is connected to a low photon density of states within the materials

Impact of electron–phonon coupling on electron transport through T-shaped arrangements of quantum dots in the Kondo regime

• Patryk Florków and
• Stanisław Lipiński

Beilstein J. Nanotechnol. 2021, 12, 1209–1225, doi:10.3762/bjnano.12.89

• very weakly in the transmission through the open dot in the case when phonons couple to IQDs. However, they are reflected clearly in the density of states (DOS) of IQDs, but this is difficult to detect in transport experiments. The single T-shaped device decoupled from phonons is characterized by SU(2

• electrodes (for the rectangular density of states of electrodes 1/2D for |E| < D, Γ = πt2/D). For the case when phonons are coupled to the open dot Γ should be replaced by , . Gdjσ denotes the Green’s function of OQDj, which according to Equation 12 can be approximately expressed as with for l = 1 and for

• the changes of conductance with the increase of λI. Figure 9b compares the density of states on the IQDs and the corresponding transmission of OQDs for λI = 0.2 (n = 1). This picture is included as a representative example illustrating the general feature of coupling of phonons to the electrons on the

First-principles study of the structural, optoelectronic and thermophysical properties of the π-SnSe for thermoelectric applications

• Muhammad Atif Sattar,
• Najwa Al Bouzieh,
• Maamar Benkraouda and
• Noureddine Amrane

Beilstein J. Nanotechnol. 2021, 12, 1101–1114, doi:10.3762/bjnano.12.82

• parameter close to the experimental value, we investigated the electronic structure of π-SnSe. The density of states (DOS) plot for the π-SnSe calculated by the meta GGA-mBJ is presented in Figure 3. The upper valence band is majorly contributed by the p states of Se and Sn atoms with a small share of Sn s

• volume is Vo = 12658.093 a.u.3. Density of states plot for the π-SnSe alloy calculated by the meta GGA-mBJ functional. Projected band structure plot for the π-SnSe calculated by the meta GGA-mBJ functional. Variation of the thermal expansion coefficient as a function of (a) temperature and (b) pressure

Molecular assemblies on surfaces: towards physical and electronic decoupling of organic molecules

• Sabine Maier and
• Meike Stöhr

Beilstein J. Nanotechnol. 2021, 12, 950–956, doi:10.3762/bjnano.12.71

• inertness and the low density of states near the Fermi level. However, the electronic decoupling efficiency also depends on the electronic structure of the 2D material. Sometimes, only molecular states in the bandgap of the 2D material can be decoupled. Moreover, ultrathin organic spacer layers can

The role of convolutional neural networks in scanning probe microscopy: a review

• Ido Azuri,
• Irit Rosenhek-Goldian,
• Neta Regev-Rudzki,
• Georg Fantner and
• Sidney R. Cohen

Beilstein J. Nanotechnol. 2021, 12, 878–901, doi:10.3762/bjnano.12.66

• was trained on simulated STEM images. Then, scanning tunneling microscopy (STM) images of the same sample were used to characterize the defects. STM images, which give the local density of states, measure not only the Si lattice, but also defect areas where this well-ordered lattice disappears. Such

Impact of GaAs(100) surface preparation on EQE of AZO/Al₂O₃/p-GaAs photovoltaic structures

• Piotr Caban,
• Rafał Pietruszka,
• Jarosław Kaszewski,
• Monika Ożga,
• Bartłomiej S. Witkowski,
• Krzysztof Kopalko,
• Piotr Kuźmiuk,
• Katarzyna Gwóźdź,
• Ewa Płaczek-Popko,
• Krystyna Lawniczak-Jablonska and
• Marek Godlewski

Beilstein J. Nanotechnol. 2021, 12, 578–592, doi:10.3762/bjnano.12.48

• = 4.50 eV [48] and effective density of states in the conduction band Nc = 2.2 × 1018 cm−3 [49], while for GaAs we used χGaAs = 4.07 eV, effective density of states in the valence band Nv = 7 × 1018 cm−3 as well as bandgap size of Eg(GaAs) = 1.42 eV [50]. The bandgap offset values were determined

Local stiffness and work function variations of hexagonal boron nitride on Cu(111)

• Abhishek Grewal,
• Yuqi Wang,
• Matthias Münks,
• Klaus Kern and
• Markus Ternes

Beilstein J. Nanotechnol. 2021, 12, 559–565, doi:10.3762/bjnano.12.46

• to the modulation of the h-BN/Cu(111) interface state as we will show below. Despite the large change in electronic density of states and, thus, tip height between the data obtained at the two different sample biases, we observe a one-to-one correspondence between the simultaneously recorded Δf

Structural and optical characteristics determined by the sputtering deposition conditions of oxide thin films

• Petronela Prepelita,
• Florin Garoi and
• Valentin Craciun

Beilstein J. Nanotechnol. 2021, 12, 354–365, doi:10.3762/bjnano.12.29

• of the oxide films. This allowed for the assessment of the permittivity and polarizability of the material, as well as the density of states in the band interval. Based on calculus, the value of the real dielectric constant (εr) can be obtained by: and the relationship to compute the imaginary

Free and partially encapsulated manganese ferrite nanoparticles in multiwall carbon nanotubes

• Saja Al-Khabouri,
• Salim Al-Harthi,
• Toru Maekawa,
• Mohamed E. Elzain,
• Ashraf Al-Hinai,
• Ahmed D. Al-Rawas,
• Abbsher M. Gismelseed,
• Ali A. Yousif and
• Myo Tay Zar Myint

Beilstein J. Nanotechnol. 2020, 11, 1891–1904, doi:10.3762/bjnano.11.170

• attributed to the attachment of manganese ferrite nanoparticles outside the tubes, which is detected by a significant decrease in the σ band emission of the ultraviolet photoemission spectroscopy signal. This is followed by an increase in the density of states at the Fermi level of the attached manganese

• are the first UPS measurements carried out for this system. Figure 1e provides the structure of the valence band of free MnFe2O4 nanoparticles. Experimental results indicate that the density of states (DOS) at the Fermi level, EF (i.e., at a zero binding energy in the UPS spectrum) is consistent with

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

• the leads by Γ = = . In the following, the wide-conduction-band approximation with a rectangular density of states is used, ραls(E) = 1/2W, where W is the half-bandwidth. To analyze correlation effects we use the slave-boson mean-field (SBMFA) approach of Kotliar and Ruckenstein (K-R) [26][64][65

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

• with m = 2 is explained by the existence of an exponential distribution of the localized sates in the bandgap of the amorphous material. In this case the I–V characteristics are described by the expression [15]: where j is the current density, Nv is the effective density of states in the valence band

Detecting stable adsorbates of (1S)-camphor on Cu(111) with Bayesian optimization

• Jari Järvi,
• Patrick Rinke and
• Milica Todorović

Beilstein J. Nanotechnol. 2020, 11, 1577–1589, doi:10.3762/bjnano.11.140

• analyzing their partial density of states (DOS) and the charge distribution with the Mulliken analysis of partial charges [40]. Camphor on Cu(111) We study the adsorption of camphor on the Cu(111) surface using two building blocks: (i) the global minimum camphor conformer and (ii) the Cu(111) surface slab

Adsorption and self-assembly of porphyrins on ultrathin CoO films on Ir(100)

• Feifei Xiang,
• Tobias Schmitt,
• Marco Raschmann and
• M. Alexander Schneider

Beilstein J. Nanotechnol. 2020, 11, 1516–1524, doi:10.3762/bjnano.11.134

• Tersoff–Hamann approximation [36]. The projected density of states (PDOS) was calculated using the same parameters. To compare the molecular PDOS on the oxide to that on the bare Ir(100), Co-DPP was put on a bridge site on three layers of Ir. The molecule and two layers of Ir were allowed to relax but no

• projected density of states of 1 on the bare metal and on the oxide layers demonstrate that also a high degree of electronic decoupling from the metal substrate is achieved at the cost of only weak hybridization with the oxide. The work therefore shows that the subtle interplay within the hierarchy of

• +2.0 V, that is, the voltages at which the images of, respectively, Figure 3a and Figure 3b. Calculated projected density of states (PDOS) near the Fermi energy of molecular orbitals with components parallel to the surface normal. Funding This work was funded by the Deutsche Forschungsgemeinschaft

Atomic defect classification of the H–Si(100) surface through multi-mode scanning probe microscopy

• Jeremiah Croshaw,
• Thomas Dienel,
• Taleana Huff and
• Robert Wolkow

Beilstein J. Nanotechnol. 2020, 11, 1346–1360, doi:10.3762/bjnano.11.119

• , with the charge-induced band bending enhancing the conductivity locally around its location, as seen in Figure 2b-2. In the constant-height STM frame in Figure 2b-3 a reduction of current due to the charge-induced band bending is again observed, along with a distortion of the density of states of the

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

•  3) are all negative, illustrating that all the doped crystal structures are stable structures. The defect binding energy decreases in the order of B, S, C, N, and F. The SnO2 doped with F has the lowest binding energy, which makes it the most stable structure. Band structure and density of states

• conduction band. The electronic structure including the energy band structure, total density of states and partial wave state density of the doped system are shown in Figure 2. For SnO2, the Fermi energy level is at the top of the valence band, indicating that the conductivity of SnO2 is low. The conduction

• needed to be solved with this method, it is sufficient to mainly discuss the photoelectric properties of doped SnO2. The total density of states of the SnO2 crystal shown in Figure 2 illustrates the that valence band of the system is divided into two parts, one from −19.1 to −14.9 eV and one between −8.1

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

• bilayer [49]. The obtained result for Li-hBN is explained by the relatively high value of the electronic density of states at the Fermi level and the significant contribution to the pairing interaction from the inter-layer electron–phonon coupling [41]. This is due to the formation of characteristic bonds

• with the increase of depairing electron correlations, the impact of vertex corrections on the ratio RΔ decreases, i.e., for μ* ≈ 0.2 the parameter differs only slightly from . Knowing the full dependence of the order parameter on the Matsubara frequency, we determined the normalized density of states

• order λ3 (Equation 12 and Equation 13) was obtained by exchanging the wave vector summation by the energy integration with constant density of states, wherein some integrals can be calculated numerically. We do not give the explicit isotropic expressions, because they are very extensive. We performed

Scanning tunneling microscopy and spectroscopy of rubrene on clean and graphene-covered metal surfaces

• Karl Rothe,
• Alexander Mehler,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2020, 11, 1157–1167, doi:10.3762/bjnano.11.100

• (Figure 1c) where one diagonal pair of phenyl groups would appear higher than the other. Such a configuration was indeed observed for a closed monolayer of C42H28 on Ag(100) [24]. However, it is difficult to infer geometric heights from STM images due to variations in the local density of states. Moreover

Monolayers of MoS₂ on Ag(111) as decoupling layers for organic molecules: resolution of electronic and vibronic states of TCNQ

• Asieh Yousofnejad,
• Gaël Reecht,
• Nils Krane,
• Christian Lotze and
• Katharina J. Franke

Beilstein J. Nanotechnol. 2020, 11, 1062–1071, doi:10.3762/bjnano.11.91

• moiré pattern bears a topographic and an electronic modulation [38], we investigate the differential conductance (dI/dV) spectra on different locations (Figure 1d). We first examine the spectrum on the top site of the moiré structure. We observe a gap in the density of states, which is flanked by an

• . The reduced spatial resolution is most probably caused by the overlap with density of states of the substrate as we are approaching the onset of the valence band of MoS2. One may suggest that the stronger localization of dI/dV intensity toward the quinone center is in agreement with the large

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

• the narrow density of states in the doped regions [37]. 8-AGNR has a linear curve, and its current at 0.3 V bias is about 20 times higher than that of the other two GNR devices. This is because of the small bandgap of 8-AGNR, which is also visible from the absorption spectrum. Figure 4b shows the I–V