Determining by Raman spectroscopy the average thickness and N-layer-specific surface coverages of MoS₂ thin films with domains much smaller than the laser spot size

• Felipe Wasem Klein,
• Jean-Roch Huntzinger,
• Vincent Astié,
• Damien Voiry,
• Romain Parret,
• Houssine Makhlouf,
• Sandrine Juillaguet,
• Jean-Manuel Decams,
• Sylvie Contreras,
• Périne Landois,
• Ahmed-Azmi Zahab,
• Jean-Louis Sauvajol and
• Matthieu Paillet

Beilstein J. Nanotechnol. 2024, 15, 279–296, doi:10.3762/bjnano.15.26

• accuracy in order to evaluate the thickness of a MoS2 flake. These phonons modes are (i) the in-plane phonon mode involving relative motion of Mo and S atoms with E′ symmetry for a monolayer (E12g for bulk) and (ii) the out-of-plane phonon mode involving only out-of-plane motions of S atoms with A′1

• resonance conditions), other bands associated to different second-order processes are observed in the Raman spectra with a strong intensity, their frequencies, widths, and intensity depending on the excitation energy [36]. In addition, resonance conditions alter the symmetry selection rules of phonons of

• that in the latter flakes, new bands, named FLA and FTA, are superimposed to the second-order Raman spectra. The FLA and FTA modes in θ-2L-MoS2 are attributed, respectively, to folded longitudinal acoustic phonons and folded transverse acoustic phonons of the monolayer due to the presence of a moiré

Nanoarchitectonics of photothermal materials to enhance the sensitivity of lateral flow assays

• Elangovan Sarathkumar,
• Rajasekharan S. Anjana and
• Ramapurath S. Jayasree

Beilstein J. Nanotechnol. 2023, 14, 988–1003, doi:10.3762/bjnano.14.82

• non-radiatively in the form of phonons. The phonons generate heat in these materials [36] (Figure 4C). Transition metal sulfide nanomaterials gain much attention in photothermal applications, because of their low cost, high biocompatibility, and considerably high PCE. Nanoparticles of copper sulfide

Isolation of cubic Si₃P₄ in the form of nanocrystals

• Polina K. Nikiforova,
• Sergei S. Bubenov,
• Vadim B. Platonov,
• Andrey S. Kumskov,
• Nikolay N. Kononov,
• Tatyana A. Kuznetsova and
• Sergey G. Dorofeev

Beilstein J. Nanotechnol. 2023, 14, 971–979, doi:10.3762/bjnano.14.80

• -ray fluorescence analyses and XRD analyses of samples annealed with phosphorus at 670, 400, and 900 °C. Calculated frequencies of optical phonons (cm−1) and preliminary designation of the experimentally observed vibrational frequencies of Si3P4 NPs. Supporting Information Supporting Information File

A graphene quantum dots–glassy carbon electrode-based electrochemical sensor for monitoring malathion

• Sanju Tanwar,
• Aditi Sharma and
• Dhirendra Mathur

Beilstein J. Nanotechnol. 2023, 14, 701–710, doi:10.3762/bjnano.14.56

• . 1385 cm−1) and G bands (ca. 1585 cm−1) with an excitation wavelength of 532 nm as shown in Figure 5b, resembling those of a standard graphitic structure [38]. As a result of defects in the sp2-hybridized GQDs structure, the D band occurs due to transverse optical (TO) phonons about the k point of the

Thermal transport in kinked nanowires through simulation

• Alexander N. Robillard,
• Graham W. Gibson and
• Ralf Meyer

Beilstein J. Nanotechnol. 2023, 14, 586–602, doi:10.3762/bjnano.14.49

• , communications, and many others [1][2][3][4][5]. In many nanoscale systems, thermal transport cannot be simply described as it would be at larger scales [6]. At such scales, the carriers of energy (such as phonons) have finite transit lengths that are no longer negligible compared to the system dimensions

• additional scattering of phonons at boundaries and cause interesting effects due to phonon reflections [12][13][14]. These effects are typically not seen at the macroscopic scale, but instead reflect the sophisticated nature of transport and finite sizes at the nano- and mesoscales. Recently, there have been

• seems to be less pronounced for systems with either long segment lengths or smaller wire radii. The impact of segment length and wire radius is similar, as both control the ratio r/l. The ratio between the radius and the segment length partially dictates the quantity of phonons that can travel large

Transferability of interatomic potentials for silicene

• Marcin Maździarz

Beilstein J. Nanotechnol. 2023, 14, 574–585, doi:10.3762/bjnano.14.48

• all previously optimized structures were computed using the metric tensor formulation of strain in the density functional perturbation theory (DFPT) [23]. The mechanical stability of the analyzed structures was verified by calculating the so-called Kelvin moduli [24][25]. To calculate the phonons, the

Conjugated photothermal materials and structure design for solar steam generation

• Chia-Yang Lin and
• Tsuyoshi Michinobu

Beilstein J. Nanotechnol. 2023, 14, 454–466, doi:10.3762/bjnano.14.36

• . The free electrons of metallic nanomaterials absorb light. This is followed by specific oscillations that give the photothermal effect. This effect originates from the surface plasmon resonance (SPR) of electrons. The SPR-based thermal energy is then transferred to lattice phonons (Figure 3a). In

• either undergo radiative relaxation in the form of photons or nonradiative relaxation in the form of phonons (heat) to release and transfer energy to impurities/defects or dangling bonds on the material surface. When energy is released in the form of phonons, local heating of the lattice is induced

Plasmonic nanotechnology for photothermal applications – an evaluation

• A. R. Indhu,
• L. Keerthana and
• Gnanaprakash Dharmalingam

Beilstein J. Nanotechnol. 2023, 14, 380–419, doi:10.3762/bjnano.14.33

• pondered on in the final section of the article, taking into account the specific requirements from different applications. Keywords: nanoparticle heating; phonons; photothermal; plasmonic; stability; surface plasmon resonance; Review 1 Introduction With an ever-increasing demand for energy and the

• mechanisms of plasmon relaxation (through non-radiative scattering) result in the eventual coupling of the scattered plasmons to phonons, their understanding is critical for designing materials for such applications. Simplistically, phonons are quantized particles or waves with a unit of vibrational energy

• Planck’s constant, and q is the wave vector of the phonon oscillations. These elementary excitation phonons are bosons with a wave vector of k = 2π/λ. Crystal defects and other such sources of anharmonicity can change their frequencies and, hence, their coupling characteristics to electrons and the

Intermodal coupling spectroscopy of mechanical modes in microcantilevers

• Ioan Ignat,
• Bernhard Schuster,
• Jonas Hafner,
• MinHee Kwon,
• Daniel Platz and
• Ulrich Schmid

Beilstein J. Nanotechnol. 2023, 14, 123–132, doi:10.3762/bjnano.14.13

• expertise. For inspiration, we turn to quantum optomechanics and its sister field of quantum electromechanics, as they both report outstanding signal-to-noise ratios [14]. In the former, a reflective mechanical resonator constitutes half of a Fabry–Pérot cavity, converting photons to phonons and vice versa

• mode splitting is a good way to measure the coupling rates. Here, the phonons from the first mode will have their frequency upconverted to the same as the second mode’s phonons, thus allowing them to interact. This pump effectively amplifies the single phonon–phonon coupling rate of the mode

Enhanced electronic transport properties of Te roll-like nanostructures

• E. R. Viana,
• N. Cifuentes and
• J. C. González

Beilstein J. Nanotechnol. 2022, 13, 1284–1291, doi:10.3762/bjnano.13.106

• , respectively, was found, demonstrating strong scattering by phonons in this temperature range. At lower temperatures, the electronic conduction is dominated by NNH in the acceptor band with a low activation energy ENNH ≈ 0.59 meV for both NWs. These values of ENNH correspond to a concentration of acceptors of

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

• intensity shown in Figure 3c. Raman scattering involves interaction between the incident light with the electrons in the ground state, the coupling between electrons in the excited state and phonons (vibrational modes), and scattered light radiation. Both charge transfer and dipole–dipole interaction can

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

• dot systems under the influence of phonons. The system is modelled by the extended Anderson–Holstein Hamiltonian. The finite-U mean-field slave boson approach is used to study many-body effects. Phonons influence both interference and correlations. Depending on the dot unperturbed energy and the

• studied in a number of papers [39][40][41][42][43][44]. Due to participation of localized phonons in single electron tunneling the phonon side bands appear in the spectral function of the dot. Interestingly, similar effects have been also observed in the rigid structures of semiconductor quantum dots

• molecule. Such a phonon interacts only with the electrons in the same QD. In the following considerations it is assumed that local phonons couple either to the open dots (OQDs) directly connected to the leads or to the dots attached to the interacting side (IQDs). The former type of coupling mainly

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

• shows the interaction between phonons and the lattice volume. It relates to the vibrational frequency change when the volume of the crystal lattice is varied. It also demonstrates the effect of temperature variations on the size or dimensions of the crystal structure. The Debye temperature can be

• conductivity value of the π-SnSe alloy is 4.63 × 1018 Ω−1·m−1·s−1 at 1000 K. In solids, the total thermal conductivity (κtot) originates due to holes/electrons drifting throughout the crystals along with phonons and heat flow. It is the combination of the electronic part of the thermal conductivity (κe) and

Is the Ne operation of the helium ion microscope suitable for electron backscatter diffraction sample preparation?

• Annalena Wolff

Beilstein J. Nanotechnol. 2021, 12, 965–983, doi:10.3762/bjnano.12.73

Properties of graphene deposited on GaN nanowires: influence of nanowire roughness, self-induced nanogating and defects

• Jakub Kierdaszuk,
• Piotr Kaźmierczak,
• Justyna Grzonka,
• Aleksandra Krajewska,
• Aleksandra Przewłoka,
• Wawrzyniec Kaszub,
• Zbigniew R. Zytkiewicz,
• Marta Sobanska,
• Maria Kamińska,
• Andrzej Wysmołek and
• Aneta Drabińska

Beilstein J. Nanotechnol. 2021, 12, 566–577, doi:10.3762/bjnano.12.47

• the scattering on phonons. Consequently, the intensity ratio of 2D and G Raman bands, R2DG, decreases when the carrier concentration increases. The histograms of R2DG for all the measured samples are presented in Figure 4. The highest standard deviation is observed for the N100 sample, which is 1.5

• and hydrogen dopants in the pyridinic position result in n-type doping [48]. Thus, defect origin and density impact graphene strain and carrier concentration as well as the interaction with the substrate. The G band is generated by the scattering on iTO or iLO phonons near the Γ point of the Brillouin

Mapping the local dielectric constant of a biological nanostructured system

• Wescley Walison Valeriano,
• Rodrigo Ribeiro Andrade,
• Juan Pablo Vasco,
• Angelo Malachias,
• Bernardo Ruegger Almeida Neves,
• Paulo Sergio Soares Guimarães and
• Wagner Nunes Rodrigues

Beilstein J. Nanotechnol. 2021, 12, 139–150, doi:10.3762/bjnano.12.11

• relative permittivity in the visible range, εr(ω→∞). For solid-state cubic crystals, the two values are related by the Lyddane–Sachs–Teller relation [23], which gives the ratio εr(0)/εr(∞) in terms of the ratio between the squared values of the long-wavelength longitudinal and transverse optical phonons in

Bio-imaging with the helium-ion microscope: A review

• Matthias Schmidt,
• James M. Byrne and
• Ilari J. Maasilta

Beilstein J. Nanotechnol. 2021, 12, 1–23, doi:10.3762/bjnano.12.1

• ). Ion collisions with a nucleus in the sample result in (back-)scattering of the primary ion, displacement of atoms in the sample, sputtering of material and generation of phonons (heat). However, incoming ions also undergo many interactions with electrons in the sample, leading to the generation of

Selective detection of complex gas mixtures using point contacts: concept, method and tools

• Alexander P. Pospelov,
• Victor I. Belan,
• Dmytro O. Harbuz,
• Volodymyr L. Vakula,
• Lyudmila V. Kamarchuk,
• Yuliya V. Volkova and
• Gennadii V. Kamarchuk

Beilstein J. Nanotechnol. 2020, 11, 1631–1643, doi:10.3762/bjnano.11.146

• contacts display quantum properties that enable the direct measurement of the interaction between electrons and various quasiparticles, such as phonons or magnons [5][6], the observation of the spectral aspects of processes occurring in the superconducting state [7][8], and the extraction of spectral

• breath, one should first consider the point-contact spectrum of the electron–phonon interaction in indium [63] (Figure 1a). The abscissa directly characterizes the energy of the phonons that interact with the electrons, which in turn obtain an excess energy of the order of eVpc when accelerated by the

• electric field in the Yanson point contact. Here e is the electron charge and Vpc is the voltage applied to the contact. Thus, each section of the curve reflects the energy parameters of a certain group of phonons. This fact allows, for example, the determination of phonon groups with energy values that

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

• Matsubara frequency. In the case of the phonon-induced superconducting state, the limitation of considerations to the order of g2 is justified by the Migdal theorem [56]. The Migdal theorem applies when the ratio λωD/εF is of the order of 0.01. This means that the energy of the phonons is so small that the

• Migdal–Eliashberg approximation is based on the replacement of the mixed Green’s function by the product of the full electron Green’s function Gk(iωn)(iωn) and the phonon propagator for the non-interacting phonons: We have extended this step. In particular, we have strictly determined the equation of

• . In addition, means the Fermi–Dirac function and is the Bose–Einstein function. The symbol represents the higher-order phonon Green’s function. It was designated by us assuming no interaction between phonons. The function Dk(ωm) is given by the formula The isotropic form of contributions of the

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

• ascribed to a combination of its rather large thickness of three atomic layers, its electronic bandgap, and its non-ionic nature. Together, these properties prohibited fast electronic relaxations into the metal and coupling to phonons, which otherwise led to lifetime broadening [27][28]. The electronic

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

• films with various compositions at temperatures at which the emission spectra were measured (20 K and 300 K), and their correlations with the energy of the incident excitation photons (3.81 eV) and the energy of photons scattered by 1LO (3.74 eV) and 2LO (3.67 eV) phonons, Table 4 summarizes the

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

• can neglect heat flow to phonons and substrate in the constriction (the main cooling of the junction comes from the diffusion of hot electrons to SN banks). In the SN bilayer DN ≫ DS and heat diffusion occurs mainly along the N layer. With above assumptions we obtain the following equation for δTe

• : 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

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

• well-understood that the underlying factors governing the optical, electronic and thermal properties of solid-state materials are strongly influenced by phonons and their spatio-temporal response toward external stimuli. Raman and photoluminescence (PL) spectroscopy has been a remarkable tool to gauge

• influenced by damping mechanisms. The FWHM is expected to be infinitesimally small for activated phonons in a dissipationless medium, and the crystal elastic waves of the harmonic oscillator model for the allowable phonon modes would thus yield an exceptionally large τ. However, natural systems inherently

• electric filed [18]. Similarly, the Raman linewidths in graphene are found to increase with defects resulting from electron–impurity and electron–phonon scattering [19]. Moreover, the Raman linewidth broadening is also attributed to the confinement of the optical phonons. Specifically, in the case of low

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

• characteristics are strongly related to the luminescence mechanism and the interaction to phonons, the effect of temperature on SPEs should be clarified. Further, spectral studies of SPEs and their coherent control are essential to establish a spin–photon interface for future quantum networks. In this respect

• phonons. The temperature dependence can result in spectral instability and diffusion. They found that the line width of ZPLs was wider than their natural linewidth, suggesting that the broadening of the line width is attributed to the phonon-mediated mechanism. Kianinia et al. [106] demonstrated stable

• lattice phonons appeared, while the g(2)(0) values and the emission lifetimes were unchanged up to 800 K. The decrease in emission intensity accompanied by heating was caused by the increase in nonradiative transition rate, and the activation energies for 1.94 eV and 1.75 eV emitters were revealed to be

Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique

• Matthias Simolka,
• Hanno Kaess and
• Kaspar Andreas Friedrich

Beilstein J. Nanotechnol. 2020, 11, 583–596, doi:10.3762/bjnano.11.46

• mechanisms are piezoelectricity, flexoelectricity and electrostriction. Further contributions are possible by deformation potential generation, electron–hole formation, coupling of electrons and phonons, electrochemical side reactions in the tip–sample junction, electrostatic interaction, and volume