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

Band tail state related photoluminescence and photoresponse of ZnMgO solid solution nanostructured films

• Vadim Morari,
• Aida Pantazi,
• Nicolai Curmei,
• Vitalie Postolache,
• Emil V. Rusu,
• Marius Enachescu,
• Ion M. Tiginyanu and
• Veaceslav V. Ursaki

Beilstein J. Nanotechnol. 2020, 11, 899–910, doi:10.3762/bjnano.11.75

• from the known values at room temperature, taking into account that the bandgap increases by around 80 meV with the decrease of temperature from 300 K to 20 K [38]. These observations are explained by the formation of large band tails in the density of states of solid solutions. It was shown that large

A Josephson junction based on a highly disordered superconductor/low-resistivity normal metal bilayer

• Pavel M. Marychev and
• Denis Yu. Vodolazov

Beilstein J. Nanotechnol. 2020, 11, 858–865, doi:10.3762/bjnano.11.71

• : where is the electron heat conductivity of the S layer in the normal state, and N(0) is the one-spin density of states on the Fermi level, is the thermal healing length, β = [γτesc 450ζ(5)T/[τ0π4Tc0], ζ(5) ≈ 1.03, τesc is the escape time of nonequilibrium phonons to the substrate, γ = 8π2Ce(Tc0)/Cp(Tc0

Adsorption behavior of tin phthalocyanine onto the (110) face of rutile TiO₂

• Lukasz Bodek,
• Mads Engelund,
• Aleksandra Cebrat and
• Bartosz Such

Beilstein J. Nanotechnol. 2020, 11, 821–828, doi:10.3762/bjnano.11.67

• . To compute the STM images, the surface integration technique of Paz and Soler was followed [17] with the Tersoff–Hamann approximation [18], assuming a proportionality factor of 1.00 nA·Å−3 for the ratio between the local density of states and the current. To mimic the effect of spatial uncertainty in

DFT calculations of the structure and stability of copper clusters on MoS₂

• Cara-Lena Nies and
• Michael Nolan

Beilstein J. Nanotechnol. 2020, 11, 391–406, doi:10.3762/bjnano.11.30

• are actually unstable. The effect of the vacancy is localised around the vacancy site. Finally, on both the pristine and the defective MoS2 monolayer, the density-of-states analysis shows that the adsorption of Cu introduces new electronic states as a result of partial Cu oxidation, but the metallic

• vacancy on the adsorption energy and geometry of single Cu adatoms and the Cu4 clusters. The results of this investigation show that the stability of small Cun clusters on a MoS2 ML is driven mainly by Cu–Cu interactions and not dependent on whether the cluster is 2D or 3D. Further, the density-of-states

• Å of the Mo–S distance in the bare ML (2.41 Å). Thus, no significant structural distortion occurs in MoS2 after Cu adsorption. We conclude, that there is no clear correlation between the Cu–S or Mo–S distances and the favourability of a binding site. Analysis of the density of states (DOS) (see

Anomalous current–voltage characteristics of SFIFS Josephson junctions with weak ferromagnetic interlayers

• Tairzhan Karabassov,
• Anastasia V. Guravova,
• Aleksei Yu. Kuzin,
• Elena A. Kazakova,
• Shiro Kawabata,
• Boris G. Lvov and
• Andrey S. Vasenko

Beilstein J. Nanotechnol. 2020, 11, 252–262, doi:10.3762/bjnano.11.19

• interlayers in the diffusive limit. The problem is solved in the framework of the nonlinear Usadel equations. We consider the case of a strong tunnel barrier such that the left SF and the right FS bilayers are decoupled. We calculate the density of states (DOS) in SF bilayers using a self-consistent numerical

• dependence [8][9][10][11][12], Josephson critical current oscillations [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41], and density of states (DOS) oscillations [42][43][44][45]. S/F hybrid structures have many promising applications in

• interesting nonmonotonic behavior for weak ferromagnetic interlayers, i.e., small enough exchange fields. The reason for this behavior is the shape of the density of states in the F layer. At small exchange fields the decay length of superconducting correlations in the ferromagnetic material, ξh, is large

Nonequilibrium Kondo effect in a graphene-coupled quantum dot in the presence of a magnetic field

• Levente Máthé and
• Ioan Grosu

Beilstein J. Nanotechnol. 2020, 11, 225–239, doi:10.3762/bjnano.11.17

• does not show up in the density of states and in the differential conductance for zero chemical potential due to the linear energy dispersion of graphene. An analytical method to calculate self-energies is also developed which can be useful in the study of graphene-based systems. Conclusion: Our

• carriers is described by a 2D Dirac-like equation. Therefore, they are often called 'relativistic' massless fermions even if they move with a speed which is about 300 times smaller than the speed of light. The density of states (DOS) is proportional to the absolute value of energy [53]. For all of the

Semitransparent Sb₂S₃ thin film solar cells by ultrasonic spray pyrolysis for use in solar windows

• Jako S. Eensalu,
• Atanas Katerski,
• Erki Kärber,
• Lothar Weinhardt,
• Monika Blum,
• Clemens Heske,
• Wanli Yang,
• Ilona Oja Acik and
• Malle Krunks

Beilstein J. Nanotechnol. 2019, 10, 2396–2409, doi:10.3762/bjnano.10.230

• , is found at 151 eV and ascribed to Sb 5s-derived states by comparison with band structure and density of states calculations [50]. Lastly, transitions from the upper valence band of Sb2S3 can be found centered at around 156 eV. These transitions were identified in line with atom-decomposed density of

• states prediction in the valence band of Sb2S3, calculated from first principles [56]. The overall spectral shape of the Sb2S3 thin films, as-prepared and after annealing, agree very well with the Sb2S3 reference powder. In contrast, no evidence for S–O bonds can be found in the Sb2S3 thin film spectra

Deterministic placement of ultra-bright near-infrared color centers in arrays of silicon carbide micropillars

• Stefania Castelletto,
• Abdul Salam Al Atem,
• Faraz Ahmed Inam,
• Hans Jürgen von Bardeleben,
• Sophie Hameau,
• Ahmed Fahad Almutairi,
• Gérard Guillot,
• Shin-ichiro Sato,
• Alberto Boretti and
• Jean Marie Bluet

Beilstein J. Nanotechnol. 2019, 10, 2383–2395, doi:10.3762/bjnano.10.229

• the local density of states of the emitters is needed. So far, other photonics structures in SiC have been shown, such as photonic crystal cavities in cubic SiC for enhancing the emission of the divacancy VSiVC and of VSi [18][46][47], microdisks for enhancing visible interface defects [48][49

Improved adsorption and degradation performance by S-doping of (001)-TiO₂

• Xiao-Yu Sun,
• Xian Zhang,
• Xiao Sun,
• Ni-Xian Qian,
• Min Wang and
• Yong-Qing Ma

Beilstein J. Nanotechnol. 2019, 10, 2116–2127, doi:10.3762/bjnano.10.206

• -S3 sample has the largest ΔR, which is consistent with the XRD results. The XP spectra do not only provide information on the binding energy of the atoms but also on the total density of states (DOS) in the valence band of TiO2 [12][49]. In order to investigate if S-doping produces energy levels

Improvement of the thermoelectric properties of a MoO₃ monolayer through oxygen vacancies

• Wenwen Zheng,
• Wei Cao,
• Ziyu Wang,
• Huixiong Deng,
• Jing Shi and
• Rui Xiong

Beilstein J. Nanotechnol. 2019, 10, 2031–2038, doi:10.3762/bjnano.10.199

• oxygen vacancies leads to a sharp peak near the Fermi level in the density of states. This proves to be an effective way to enhance the ZT values of the MoO3 monolayer. The increased ZT values can reach 0.84 (x-axis) and 0.12 (y-axis) at 300 K. Keywords: Boltzmann transport theory; first-principles

• of the relaxation time τ, we apply the deformation potential (DP) theory [25] where τ is estimated by τ = μm*/e. The carrier mobility μ2D in 2D materials is given by Where m* is the effective mass and md is the density of states (DOS) mass determined by E1 is the DP constant and C2D is the elastic

• ratio of the Seebeck coefficient and the electrical conductivity along the x-axis and the y-axis at room temperature. Calculated (a) total electronic density of states (DOS) and projected DOS for (b) Mo and (c) O atoms of the MoO3 monolayer. The insets of (b) and (c) show the total charge density from

First principles modeling of pure black phosphorus devices under pressure

• Ximing Rong,
• Zhizhou Yu,
• Zewen Wu,
• Junjun Li,
• Bin Wang and
• Yin Wang

Beilstein J. Nanotechnol. 2019, 10, 1943–1951, doi:10.3762/bjnano.10.190

• zigzag and armchair BP devices can be understood by analyzing the band alignment of the system. This can be shown intuitively by plotting the partial density of states (PDOS) in the scattering region along the transport direction. Figure 5a and Figure 5b show the PDOS at the Fermi level of zigzag BP