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

• the modes with strong electron–phonon coupling. Keywords: decoupling layer; molybdenum disulfide (MoS2); scanning tunneling microscopy, tetracyanoquinodimethane (TCNQ); vibronic states; Introduction When molecules are adsorbed on metal surfaces, their electronic states are strongly perturbed by

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

• PL bands at lower photon energies represent the LO-phonon replicas of the AX and D0X bands at 3.29–3.31 eV, and the 2LO-phonon replicas at 3.22–3.24 eV. The PL band at 3.359 eV in films comes also from the recombination of D0X excitons in ZnO crystallites, while the PL bands at 3.324 eV, 3.267 eV and

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

• equation where Tc0 is the critical temperature of the single S layer. We assume that Δ is nonzero only in the S layer because of the absence of attractive phonon-mediated electron–electron coupling in the N layer. Equation 1 and Equation 2 are supplemented by the Kupriyanov–Lukichev boundary conditions [16

• ) model [24][25] for the SN-S-SN junction. We suppose that electron temperature Te = T + δTe and phonon temperature Tp = T + δTp are close to the substrate temperature, δTe, δTp ≪ T and do not vary along the thickness. In the N layer the proximity-induced gap (minigap) is small, and, due to the inverse

• ) is the ratio between electron and phonon heat capacity at T = Tc0 and τ0 determines the strength of electron–phonon inelastic scattering in the S and the N layer (see Equations 4 and 6 in [25]). For τ0 we use the smallest time for S and N materials due to the assumably good transfer of electrons

Epitaxial growth and superconducting properties of thin-film PdFe/VN and VN/PdFe bilayers on MgO(001) substrates

• Wael M. Mohammed,
• Igor V. Yanilkin,
• Amir I. Gumarov,
• Airat G. Kiiamov,
• Roman V. Yusupov and
• Lenar R. Tagirov

Beilstein J. Nanotechnol. 2020, 11, 807–813, doi:10.3762/bjnano.11.65

• R(T) behavior of VN/MgO(011) samples in [42], which was explained by a change in the electron/phonon scattering amplitude upon the structural phase transition from cubic to tetragonal at Ts = 250 K. Below 50 K the R(T) dependence saturates approaching the residual resistance originating, in general

Light–matter interactions in two-dimensional layered WSe₂ for gauging evolution of phonon dynamics

• Avra S. Bandyopadhyay,
• Chandan Biswas and
• Anupama B. Kaul

Beilstein J. Nanotechnol. 2020, 11, 782–797, doi:10.3762/bjnano.11.63

• of Electrical and Computer Engineering, University of Texas, El Paso, TX 79968, United States 10.3762/bjnano.11.63 Abstract Phonon dynamics is explored in mechanically exfoliated two-dimensional WSe2 using temperature-dependent and laser-power-dependent Raman and photoluminescence (PL) spectroscopy

• . From this analysis, phonon lifetime in the Raman active modes and phonon concentration, as correlated to the energy parameter E0, were calculated as a function of the laser power, P, and substrate temperature, T. For monolayer WSe2, from the power dependence it was determined that the phonon lifetime

• for the in-plane vibrational mode was twice that of the out-of-plane vibrational mode for P in the range from 0.308 mW up to 3.35 mW. On the other hand, the corresponding relationship for the temperature analysis showed that the phonon lifetime for the in-plane vibrational mode lies within 1.42× to

Hexagonal boron nitride: a review of the emerging material platform for single-photon sources and the spin–photon interface

• Stefania Castelletto,
• Faraz A. Inam,
• Shin-ichiro Sato and
• Alberto Boretti

Beilstein J. Nanotechnol. 2020, 11, 740–769, doi:10.3762/bjnano.11.61

• criteria to benchmark the performance of a solid-state SPS to be considered suitable for applications in quantum technology [7][8][80]. These include the following: photo-stable emission without blinking or photo-bleaching; narrow bandwidth with most of the emission in the zero phonon line (ZPL), which is

• criteria for spin–photon-phonon entanglement distribution are high electron spin coherence time T2 (approaching T2 spin-lattice relaxation time) and strain and electrical control of the spin transition and optical transition resonances. The key requirements can be restrictive depending on the applications

• photons exciting electrons to a higher energy level in an atom. This photo-excitation is then followed by various relaxation processes. During these relaxation processes, other photons can be re-irradiated. One interesting parameter is the zero-phonon line (ZPL), which is the difference between the lowest

Soybean-derived blue photoluminescent carbon dots

• Shanshan Wang,
• Wei Sun,
• Dong-sheng Yang and
• Fuqian Yang

Beilstein J. Nanotechnol. 2020, 11, 606–619, doi:10.3762/bjnano.11.48

• phonon, is the phonon energy, and k is the Boltzmann constant. It is evident that increasing temperature leads to the decrease of the energy gap. The CDs become conductive at temperatures larger than the critical temperture and lose the PL charactersistic, as demonstrated by the annealed-CDs due to

Electrochemically derived functionalized graphene for bulk production of hydrogen peroxide

• Munaiah Yeddala,
• Pallavi Thakur,
• Anugraha A and
• Tharangattu N. Narayanan

Beilstein J. Nanotechnol. 2020, 11, 432–442, doi:10.3762/bjnano.11.34

• experiment. The important Raman peaks are marked in the figure and the shoulder peak in “G” is due to the additional single phonon intra-valley scattering process (named as D’) which is due to the presence of defects. However, the FTIR spectrum (see Figure S4b) shows evidence for the formation of OH

High dynamic resistance elements based on a Josephson junction array

• Konstantin Yu. Arutyunov and
• Janne S. Lehtinen

Beilstein J. Nanotechnol. 2020, 11, 417–420, doi:10.3762/bjnano.11.32

• fluctuations. The absence of dissipation makes such elements very useful for experimental studies of mesoscopic scale objects at ultralow temperature applications, where even a very small amount of Johnson noise may overheat electrons above the phonon bath. However, the non-linearity of a SIS junction I–V

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

• for the gapped graphene electrodes within the massless gap scenario. The systems present a high heat-to-electricity conversion efficiency at low temperature, for which the phonon contribution can be neglected [38][39]. The analytical approaches to Kondo physics of magnetic impurities in graphene

Size effects of graphene nanoplatelets on the properties of high-density polyethylene nanocomposites: morphological, thermal, electrical, and mechanical characterization

• Tuba Evgin,
• Alpaslan Turgut,
• Georges Hamaoui,
• Zdenko Spitalsky,
• Nicolas Horny,
• Matej Micusik,
• Mihai Chirtoc,
• Mehmet Sarikanat and
• Maria Omastova

Beilstein J. Nanotechnol. 2020, 11, 167–179, doi:10.3762/bjnano.11.14

• phonon transfer between the HDPE matrix and the GnPs fillers [21][34][35]. Furthermore, GnPs with larger lateral size showed a larger enhancement of the thermal conductivity. A similar lateral-size effect of GnPs was also observed in earlier studies [13][18][21]. One reason was that the fillers could

• more easily contact each other to create a more conductive network within the nanocomposites, resulting in a higher thermal conductivity [13][21][36]. Another reason was that a small lateral size increased phonon scattering at the matrix-bonded interface, resulting in a lower thermal conductivity of

• enhancement. The thermal conductivity of the nanocomposites with a larger lateral size could be further increased by forming a more effective thermal conductive pathway and reducing phonon scattering at the matrix/filler interface. In addition, to obtain the same thermal conductivity enhancement, larger

Recent progress in perovskite solar cells: the perovskite layer

• Xianfeng Dai,
• Ke Xu and
• Fanan Wei

Beilstein J. Nanotechnol. 2020, 11, 51–60, doi:10.3762/bjnano.11.5

• the mobility, the lifetime and the vertical diffusion length of the charge carriers in the 2/3D perovskite. Figure 4h–k indicates that the 2D/3D perovskite (x = 0.03) has a better crystallinity than the pure 3D material because of its clearer crystal lattice phonon features. These factors greatly

Self-assembly of a terbium(III) 1D coordination polymer on mica

• Quentin Evrard,
• Giuseppe Cucinotta,
• Felix Houard,
• Guillaume Calvez,
• Yan Suffren,
• Carole Daiguebonne,
• Olivier Guillou,
• Andrea Caneschi,
• Matteo Mannini and
• Kevin Bernot

Beilstein J. Nanotechnol. 2019, 10, 2440–2448, doi:10.3762/bjnano.10.234

• layering on the mica substrate. This may be a result of i) the geometric distribution of the Tb coordination environment in the deposits similar to what has been observed when SMMs are dissolved in liquid matrixes [27] or ii) a modification of the spin–phonon coupling, as the phonon bath of such deposits

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

• . Current studies aim to determine more accurately the quantum properties of these defects by using more recent methods of single-photon detection and single-color center isolation, and quantum coherent spin control. The parameters used to describe the quantum properties of color centers include zero-phonon

• line (ZPL) [22], Debye–Waller factor (DWF) [23][24], zero-field-splitting (ZFS) [25] and optically detected magnetic resonance (ODMR) [26]. The ZPL and the phonon sideband together determine the line shape of individual light-absorbing and emitting molecules [22]. The DWF describes the thermal motion

• attenuation of X-ray or coherent neutron scattering [23][24]. The DWF can be estimated as the ratio of the ZPL PL emission, compared to the total PL emission, which is the combination of the ZPL PL emission and the phonon-broadened PL. The ZFS refers to the lifting of degeneracy in the absence of a magnetic

Ion mobility and material transport on KBr in air as a function of the relative humidity

• Dominik J. Kirpal,
• Korbinian Pürckhauer,
• Alfred J. Weymouth and
• Franz J. Giessibl

Beilstein J. Nanotechnol. 2019, 10, 2084–2093, doi:10.3762/bjnano.10.203

• overcome the energy barrier, kB the Boltzmann constant and T the temperature. We assume an attempt rate of ν = 1013 s−1, which is in the order of magnitude of a KBr phonon [31], equal for both transitions. This differential equation can be solved by an exponential decaying function of the form N(t) = N0

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

• (harmonic) interatomic force constants (IFCs), and third-order (anharmonic) IFCs are obtained from the ShengBTE code [28] with the maximum atomic interaction distance of the sixth neighbor in the 4 × 4 × 1 supercell. Here, a dense phonon q-grid of 52 × 52 × 1 is used to compute the thermal conductivity of

• the HSE06 hybrid functional potential, we use the PBE potential to get the electrical transport properties of the MoO3 monolayer in the following work. The phonon dispersion in the high-symmetry directions of the first Brillouin zone of the MoO3 monolayer is plotted in Figure 1c. There is no imaginary

• frequency, ensuring the stability of the MoO3 monolayer. It is well known that the acoustical phonon branches possess large group velocities and mainly determine the thermal conductivity of the lattice [32]. As the dashed lines emphasize in Figure 1c, the acoustic phonon group velocity along the Γ–Y

Remarkable electronic and optical anisotropy of layered 1T’-WTe₂ 2D materials

• Qiankun Zhang,
• Rongjie Zhang,
• Jiancui Chen,
• Wanfu Shen,
• Chunhua An,
• Xiaodong Hu,
• Mingli Dong,
• Jing Liu and
• Lianqing Zhu

Beilstein J. Nanotechnol. 2019, 10, 1745–1753, doi:10.3762/bjnano.10.170

• anisotropic acoustic phonon scatter and elliptic elastic constants (both are relevant to the anisotropic crystalline structure) [31]. One of the consequences of an anisotropic carrier mobility is the anisotropic resistance. Therefore, we also performed angle-resolved DC conductance measurements on the 1T

High-temperature resistive gas sensors based on ZnO/SiC nanocomposites

• Vadim B. Platonov,
• Marina N. Rumyantseva,
• Alexander S. Frolov,
• Alexey D. Yapryntsev and
• Alexander M. Gaskov

Beilstein J. Nanotechnol. 2019, 10, 1537–1547, doi:10.3762/bjnano.10.151

• of zinc oxide contains an intense broad signal, corresponding to the stretching vibrations of Zn–O bonds (635–400 cm−1). The above spectrum also shows the signals from the multi-phonon vibrational modes of the ZnO lattice (990 and 870 cm−1). In accordance with the literature data, such oscillations

Superconducting switching due to a triplet component in the Pb/Cu/Ni/Cu/Co₂Cr_1−xFe_xAl_y spin-valve structure

• Andrey Andreevich Kamashev,
• Nadir Nurgayazovich Garif’yanov,
• Aidar Azatovich Validov,
• Joachim Schumann,
• Vladislav Kataev,
• Bernd Büchner,
• Yakov Victorovich Fominov and
• Ilgiz Abdulsamatovich Garifullin

Beilstein J. Nanotechnol. 2019, 10, 1458–1463, doi:10.3762/bjnano.10.144

• mechanically removed from the areas where the golden wires should be attached using a silver paste. The quality of the Pb layer can be judged from the residual resistivity ratio (RRR): Here, R(T) is the measured resistance at a given temperature T, ρph(300 K) is the phonon contribution to the specific

Kelvin probe force microscopy of the nanoscale electrical surface potential barrier of metal/semiconductor interfaces in ambient atmosphere

• Petr Knotek,
• Tomáš Plecháček,
• Jan Smolík,
• Petr Kutálek,
• Filip Dvořák,
• Milan Vlček,
• Jiří Navrátil and
• Čestmír Drašar

Beilstein J. Nanotechnol. 2019, 10, 1401–1411, doi:10.3762/bjnano.10.138

• (NIs/NPs) into the bulk semiconducting matrices has been proposed [4][5][6] and supported in theoretical works [7][8][9]. Such NIs or NPs are able to enhance ZT via a reduction of the thermal conductivity by phonon scattering [10][11][12][13][14], by modulated carrier doping or by the carrier energy

Construction of a 0D/1D composite based on Au nanoparticles/CuBi₂O₄ microrods for efficient visible-light-driven photocatalytic activity

• Weilong Shi,
• Mingyang Li,
• Hongji Ren,
• Feng Guo,
• Xiliu Huang,
• Yu Shi and
• Yubin Tang

Beilstein J. Nanotechnol. 2019, 10, 1360–1367, doi:10.3762/bjnano.10.134

• light. Among these compounds, the spinel-type compound CuBi2O4 has attracted much attention because of its low phonon energy, strong visible-light response and adequate thermal stability [11][12]. Because of these attractive features, CuBi2O4 has been widely studied as a photocatalytic material in the

Synthesis and characterization of quaternary La(Sr)S–TaS₂ misfit-layered nanotubes

• Marco Serra,
• Erumpukuthickal Ashokkumar Anumol,
• Dalit Stolovas,
• Iddo Pinkas,
• Ernesto Joselevich,
• Reshef Tenne,
• Andrey Enyashin and
• Francis Leonard Deepak

Beilstein J. Nanotechnol. 2019, 10, 1112–1124, doi:10.3762/bjnano.10.111

• cm−1 was assigned to the two-phonon bands of the TaS2 slab. The 125 cm−1 peak was assigned to the out-of-phase vibration of the LaS lattice. On the other hand, the 150 cm−1 peak was assigned to the in-phase phonon of LaS. The E2g mode of the TaS2 in the MLC lattice is found in the energy range of

• about 321–325 cm−1. This peak is blue-shifted compared to the pure TaS2 (279 cm−1), which is attributed to the characteristic charge transfer from the LaS slab to that of TaS2. The broad band between ≈240 and 304 cm−1 is attributed to the two-phonon band [52], whereas the 400 cm−1 transition was

CuInSe₂ quantum dots grown by molecular beam epitaxy on amorphous SiO₂ surfaces

• Henrique Limborço,
• Pedro M.P. Salomé,
• Rodrigo Ribeiro-Andrade,
• Jennifer P. Teixeira,
• Nicoleta Nicoara,
• Kamal Abderrafi,
• Joaquim P. Leitão,
• Juan C. Gonzalez and
• Sascha Sadewasser

Beilstein J. Nanotechnol. 2019, 10, 1103–1111, doi:10.3762/bjnano.10.110

• substrates, bare (as-grown) nanodot samples and CdS-covered nanodot samples, as shown in Figure 4. The PL spectra of the bare Si and CIS samples, Figure 4a, show only the common sharp lines related with the Si substrate [41][42]. The observed lines correspond to the phonon replicas (TA, TO and TO+OΓ) of the

• radiative recombination of free excitons (FE) and of bound excitons (B), as well as the no-phonon line of the bound exciton (BNP) as confirmed from PL measurements performed under the same experimental conditions of a Si substrate. After the deposition of a CdS layer on top of the three as-grown nanodot

Electronic properties of several two dimensional halides from ab initio calculations

• Mohamed Barhoumi,
• Ali Abboud,
• Lamjed Debbichi,
• Moncef Said,
• Torbjörn Björkman,
• Dario Rocca and
• Sébastien Lebègue

Beilstein J. Nanotechnol. 2019, 10, 823–832, doi:10.3762/bjnano.10.82

• electronic bandgaps, as obtained with the HSE hybrid functional, range between 3.0 and 7.5 eV and that their phonon spectra are dynamically stable. Additionally, we show that under an external electric field some of these systems exhibit a semiconductor-to-metal transition. Keywords: density functional

• performing phonon calculations. These studies were conducted on bulk materials but little is known on the structural and electronic properties of the corresponding isolated layers. By using a datamining procedure some halides were identified as possible 2D materials [14] but their dynamical stability and

• images. Geometries (cell and atom positions) were relaxed with a threshold on forces of 10−6 eV/Å. The phonon dispersion curves of the single layers, as presented in Supporting Information File 1, were determined with the PHONOPY code [39] with a 5 × 5 × 1 supercell using density functional perturbation

Ultrasonication-assisted synthesis of CsPbBr₃ and Cs₄PbBr₆ perovskite nanocrystals and their reversible transformation

• Longshi Rao,
• Xinrui Ding,
• Xuewei Du,
• Guanwei Liang,
• Yong Tang,
• Kairui Tang and
• Jin Z. Zhang

Beilstein J. Nanotechnol. 2019, 10, 666–676, doi:10.3762/bjnano.10.66

• ) structures of Cs4PbX6 NCs can be achieved, demonstrating a crystalline structure with well-separated octahedra [PbBr6]4− isolated by Cs+ ions [12][13]. This specific structure is expected to result in strong quantum confinement and electron–phonon interactions. This inspires researchers to further explore