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

• 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

• role of the cavity mode in cavity optomechanics, respectively. Xi and Xj are their respective amplitudes, is the amplitude of the pump in meters, is the directional single phonon–phonon parametric coupling rate in Hz/meters. The last term describes a small signal Vsense, proportional to the voltage

• couplings at the same time. Innumerable applications include those studied in optomechanics and electromechanics, as well as theoretical implementations yet to be seen in practice, all powered by phonon–phonon interactions. Not only bringing improvements to common AFM tools, but providing opportunities for

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

• cm2/Vs at 5 K. The thermal ionization of shallow acceptors, with small ionization energy between 2 and 4 meV, leads to free-hole conduction at high temperatures. The free-hole mobility follows a negative power-law temperature behavior, with an exponent between −1.28 and −1.42, indicating strong phonon

• the mobility is mainly limited by phonon scattering at high temperatures, α is close to 3/2 [33][34]. Nveff is the effective density of states of the valence band, EA is the shallow acceptor ionization energy [33], and kB is Boltzmann’s constant. At lower temperatures, most of the free holes are

Analytical and numerical design of a hybrid Fabry–Perot plano-concave microcavity for hexagonal boron nitride

• Felipe Ortiz-Huerta and
• Karina Garay-Palmett

Beilstein J. Nanotechnol. 2022, 13, 1030–1037, doi:10.3762/bjnano.13.90

• our system (2D material + DBR stack) to have a maximum reflectivity at the center wavelength of 637 nm. The selected wavelength of our system falls within the typical emission rates of the zero-phonon line (ZPL) of SPEs in hBN (500–800 nm). A quarter-wavelength thickness is conveniently chosen for the

Numerical study on all-optical modulation characteristics of quantum cascade lasers

• Biao Wei,
• Haijun Zhou,
• Guangxiang Li and
• Bin Tang

Beilstein J. Nanotechnol. 2022, 13, 1011–1019, doi:10.3762/bjnano.13.88

• standard 35-stage In0.52Al0.48As/In0.53Ga0.47As type-I four-level Fabry–Perot QCL based on a two-phonon-resonance design [27]. Current injection efficiency is defined as the ratio of current to total current injected into the upper subband of the QCL in the active region, which is close to 56%. The QCL

Efficiency of electron cooling in cold-electron bolometers with traps

• Dmitrii A. Pimanov,
• Vladimir A. Frost,
• Anton V. Blagodatkin,
• Anna V. Gordeeva,
• Andrey L. Pankratov and
• Leonid S. Kuzmin

Beilstein J. Nanotechnol. 2022, 13, 896–901, doi:10.3762/bjnano.13.80

• superconductor/ferromagnet hybrid absorbers based on Al/Fe films, as the previous samples. However, there are different oxidation parameters. This work aims to improve our new fit methodology, which takes into account both leakage and Andreev currents and also uses the sixth power of phonon and electron

• solves the equations of the stationary CEB theory [16]. We use the approach based on solving the heat balance equation [7]: where PN is Joule heating in the absorber. is the heat flux between electron and phonon subsystems, taken with the sixth power [17] due to low electron temperature in our

• experiments (in our previous calculations we have used the fifth power). Σ is the electron–phonon coupling constant; it has different values, depending on the electron temperature [17]. VN is the absorber volume, Pcool is the direct electron cooling power, PS is the net power transferred to the S-electrode

Numerical modeling of a multi-frequency receiving system based on an array of dipole antennas for LSPE-SWIPE

• Alexander V. Chiginev,
• Anton V. Blagodatkin,
• Dmitrii A. Pimanov,
• Ekaterina A. Matrozova,
• Anna V. Gordeeva,
• Andrey L. Pankratov and
• Leonid S. Kuzmin

Beilstein J. Nanotechnol. 2022, 13, 865–872, doi:10.3762/bjnano.13.77

• electronic subsystem of the CEB absorber [6][7][8]. Another key advantage for balloon and space missions is the high immunity of CEB against cosmic rays [9] due to a double protection given by the extremely small volume of the absorber and decoupling of electron and phonon systems. One of the advantages of

Optimizing PMMA solutions to suppress contamination in the transfer of CVD graphene for batch production

• Chun-Da Liao,
• Andrea Capasso,
• Tiago Queirós,
• Telma Domingues,
• Fatima Cerqueira,
• Nicoleta Nicoara,
• Jérôme Borme,
• Paulo Freitas and
• Pedro Alpuim

Beilstein J. Nanotechnol. 2022, 13, 796–806, doi:10.3762/bjnano.13.70

• ± 3.0 cm−1 (Figure 2f,i), implying high-quality monolayer graphene. Together, the data further support uniformity and crystallinity of the sample. The G phonon band arises from double degeneracy of iTO and iLO phonon modes (E2g symmetry) at the Brillouin zone center, which is an in-plane vibration of

• the PMMA mixture, we consider that the differences in Raman spectra between the different samples can be attributed to adsorbed PMMA residues. Such residues could absorb water and oxygen molecules, conferring p-type doping to graphene [29]. Conversely, by tracking the G phonon band features in Raman

• ). The broader G phonon band observed for the B2 samples reveals that a significantly higher number of inter-band decay pathways are available due to a lower Pauli blocking threshold [23] (equivalent to twice |EF|), further indicating that the p-type doping caused by adsorbed PMMA is less intense for the

Efficient liquid exfoliation of KP₁₅ nanowires aided by Hansen's empirical theory

• Zhaoxuan Huang,
• Zhikang Jiang,
• Nan Tian,
• Disheng Yao,
• Fei Long,
• Yanhan Yang and
• Danmin Liu

Beilstein J. Nanotechnol. 2022, 13, 788–795, doi:10.3762/bjnano.13.69

• value below 100 nm. The thinnest KP15 nanowires reached 5.1 nm and had smooth boundaries. Meanwhile, strong temperature-dependent Raman response in exfoliated KP15 nanowires has been observed, which indicates a strong phonon–phonon coupling in those nanowires. This is helpful for non-invasive

• reached 5.1 nm and had smooth boundaries. Meanwhile, a strong temperature-dependent Raman response was found in exfoliated KP15 nanowires. This indicates a strong phonon–phonon coupling in KP15 nanowires, which favors non-invasive temperature measurements of KP15 nanodevices. Methods Synthesis of KP15

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

• relation is given by: We defined the cutoff energy ΩBCS related to the upper limit of the phonon spectrum. In the following, we use ΩBCS = 100kBTc, and the coupling constant λ, which can be eliminated for the bulk superconductor in favor of the critical temperature Tc. After solving the fully self

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

• contribute actively to electron–phonon coupling [36]. With a face-on orientation of the CuPc molecules at the MoSe2 monolayer, the delocalized π electrons of CuPc overlap efficiently with the electron cloud of the MoSe2 monolayer. As the HOMO of CuPc is close to the valence band of the MoSe2 monolayer as

• , 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

Effect of lubricants on the rotational transmission between solid-state gears

• Huang-Hsiang Lin,
• Jonathan Heinze,
• Alexander Croy,
• Rafael Gutiérrez and
• Gianaurelio Cuniberti

Beilstein J. Nanotechnol. 2022, 13, 54–62, doi:10.3762/bjnano.13.3

• multiscale simulation involving continuum modelling in combination with MD simulations would be helpful to connect the atomistic description with macroscopic behavior, for example, as given by the Stribeck curve [5]. A substrate can also provide significant friction due to electron or phonon excitations [65

Plasmon-enhanced photoluminescence from TiO₂ and TeO₂ thin films doped by Eu³⁺ for optoelectronic applications

• Marcin Łapiński,
• Jakub Czubek,
• Katarzyna Drozdowska,
• Anna Synak,
• Wojciech Sadowski and
• Barbara Kościelska

Beilstein J. Nanotechnol. 2021, 12, 1271–1278, doi:10.3762/bjnano.12.94

• popular and widely used oxide material as matrix for rare-earth ions [9][10][11][12][13]. Tellurium dioxide can be also considered as excellent in hosting rare-earth ions because of its low phonon energy (ca. 700–800 cm−1), which allows to minimize non-radiative losses [14][15][16]. Modification of oxide

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

• strength of electron–phonon interaction, the system is occupied by a different number of electrons that effectively interact with each other repulsively or attractively. This leads, together with the interference effects, to different spin or charge Fano–Kondo effects. Keywords: Fano effect; Kondo effect

• ultrafast sensors, actuators, and signal processing components. Of special interest are molecular systems because molecules due to their softness easily deform during tunneling processes, giving rise to excitation of local phonon modes. The polaronic transport through molecular systems has been recently

• 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

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

• from Figure 6a that for a fixed pressure, the CV curve grows sharply up to 300 K then the value of CV gradually raises. Afterward, at a higher temperature range, the CV curve keeps a continuing pace and tends to reach the Dulong–Petit limit, revealing that at a high-temperature range all the phonon

• large entropy impact which accelerates the phonon–phonon scattering process. The total thermal conductivity (κtot) for the π-SnSe alloy is also plotted and presented in Figure 9c. It can be noted that initially, by the increase in temperature, κtot decreases and reaches its minimum value of 1.089 W·m−1

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

• phonon scattering effect from the few point defects introduced. For higher doses above ca. 2 × 1016 ions/cm2, complete amorphization of the material occurred, although it was noted that the overall morphology of the structure was unaffected. This ability to locally tune the thermal conductivity by

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

• a deep understanding of the phenomena occurring on such interface. One of the most common experimental techniques for studying properties of graphene is Raman spectroscopy [10]. Non-invasive measurements of inelastic light scattering give an insight into the phonon structure of graphene. The

• of strain, and the value of 2D band energy for unstrained graphene was reported to be 2677.6 cm−1 [14]. Positive values of Δε correspond to tensile strain while negative values correspond to compressive strain. The Grüneisen parameter determines the change rate of a given phonon frequency in a

• equal to 1583.5 cm–1 [14]. The sensitivity of the G band energy on the carrier concentration is caused by the presence of a Kohn anomaly near the Γ point in the phonon band structure of graphene [15]. Consequently, the G band energy significantly increases with an increasing concentration of both

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

• for graphene and MoS2-based electronics utilising the small lattice mismatch, the large optical phonon modes, and particularly the large bandgap [3][4][5][6][7][8][9][10]. Furthermore, when grown on metal substrates h-BN can be used as a nanoscale template for atoms, molecules, and nanostructures with

ZnO and MXenes as electrode materials for supercapacitor devices

• Ameen Uddin Ammar,
• Ipek Deniz Yildirim,
• Feray Bakan and
• Emre Erdem

Beilstein J. Nanotechnol. 2021, 12, 49–57, doi:10.3762/bjnano.12.4

• , which is expected due to the quantum confinement effect [13]. Another crucially important optical characterization technique for the investigation of defects is Raman spectroscopy. The phonon vibration modes are highly sensitive to the existence of point defects, which are reflected in distinct spectral

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

• associated with the given resonances. At this point it should be mentioned that one should look at the high-temperature results in Figure 6b with some caution, in particular, at those that concern the thermopower. Inelastic processes, for example, these resulting from electron–phonon interaction are

• neglected in our calculations, which is justified at extremely low temperatures. At higher temperatures, however, they may play a role [75][76]. Some justification for the neglect of electron–phonon coupling is that, as shown in [77][78][79][80], the electron–phonon mean free path in nanoscale carbon tubes

• and ribbons is tens of micrometers even at room temperature. It has been also shown that the phonon contribution to the thermopower of quantum dots is greatly suppressed [81]. The Landauer-type formulas we use strictly apply only to elastic transport. The electron part of the thermopower is very

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

• are excited and transition to a nonequilibrium state. Then, the electrons gradually relax as they interact with quantum quasiparticle excitations and other objects. This process is fundamental for Yanson spectroscopy of electron–phonon interactions [30] and is responsible for the unique properties of

• quasiparticle excitations using point contacts. This was clearly demonstrated for the first time by Yanson while studying electron–phonon interactions in metals [60]. When a current flows through Yanson point contacts, a unique condition for the manifestation of the quantum properties of these objects arises

• manifestation of the energy parameters of this interaction in the electrical characteristics of the point contacts. Due to this phenomenon, the spectrum of the electron–phonon interaction in metals [5], superconductors [8][61], and even in more complex compounds such as organic conductors [62] can be easily

High-responsivity hybrid α-Ag₂S/Si photodetector prepared by pulsed laser ablation in liquid

• Raid A. Ismail,
• Hanan A. Rawdhan and
• Duha S. Ahmed

Beilstein J. Nanotechnol. 2020, 11, 1596–1607, doi:10.3762/bjnano.11.142

• with a monoclinic structure and that crystallinity of the nanoparticles was improved after adding CTAB. Raman studies revealed the presence of peaks related to Ag–S bonds (Ag modes) and the longitudinal optical phonon 2LO mode. Scanning electron microscopy investigations confirmed the production of

• reported data [24]. Figure 4 shows the Raman spectra of Ag2S NPs synthesized in Tu solution with and without CTAB. Four vibration modes were assigned to Ag2S. The peaks at 45 and 65 cm−1 are related to Ag–S bonds (Ag modes) [25]. The third peak at 480 cm−1 was indexed to the longitudinal optical phonon 2LO

• –S bonds and the second-order longitudinal optical phonon 2LO mode; their intensity increased when CTAB was added to Tu. FTIR data revealed the presence of a Ag–S bond located at 510 cm−1. The electrical properties of the Ag2S/Si heterojunction were significantly enhanced after the addition of CTAB

Optically and electrically driven nanoantennas

• Monika Fleischer,
• Dai Zhang and
• Alfred J. Meixner

Beilstein J. Nanotechnol. 2020, 11, 1542–1545, doi:10.3762/bjnano.11.136

• of their optical phonon response. High local field enhancement is likewise required in TERS experiments, where a tip with a hotspot located at its apex is scanned across a sample surface. The performance of a TERS measurement is closely related to the quality of the tip [46]. Therefore, researchers

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

• of electron–phonon interaction cannot be omitted. This is evidenced by the very high value of the ratio λωD/εF ≈ 0.46, where λ is the electron–phonon coupling constant, ωD is the Debye frequency, and εF represents the Fermi energy. Due to nonadiabatic effects, the phonon–induced superconducting state

• percent. Keywords: critical temperature; electron–phonon interaction; Li-hBN bilayer; Li-intercalated hexagonal boron nitride (Li-hBN); nonadiabatic superconductivity; vertex corrections; Introduction Low-dimensional systems such as graphene [1][2][3][4][5], silicene [6], borophene [7][8], and

• 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

Revealing the local crystallinity of single silicon core–shell nanowires using tip-enhanced Raman spectroscopy

• Marius van den Berg,
• Ardeshir Moeinian,
• Arne Kobald,
• Yu-Ting Chen,
• Anke Horneber,
• Steffen Strehle,
• Alfred J. Meixner and
• Dai Zhang

Beilstein J. Nanotechnol. 2020, 11, 1147–1156, doi:10.3762/bjnano.11.99

• structure and phases of silicon by measuring its Raman peaks along a silicon wire prepared under high pressure. They found a shift of the transverse optical (TO) phonon peak along the wire, which could be attributed to a non-uniform growth of the nanowire and different crystalline phases. Agbo et al. showed

• , Figure 5d, and Figure S1b in Supporting Information File 1). Beeman et al. [22] suggested to use the root mean square bond-angle distortion ΔΘ to evaluate the crystalline and amorphous fractions of Si, which can be calculated using the full width half maximum (FWHM, in cm−1) of the one-phonon Raman peak

Photothermally active nanoparticles as a promising tool for eliminating bacteria and biofilms

• Mykola Borzenkov,
• Piersandro Pallavicini,
• Angelo Taglietti,
• Laura D’Alfonso,
• Maddalena Collini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2020, 11, 1134–1146, doi:10.3762/bjnano.11.98

• photothermal effect under NIR laser irradiation. Carbon nanotubes are another valuable class of nanomaterials. They have high photothermal efficiency under NIR irradiation which excites the longitudinal phonon resonance along the nanotube. The resonance peaks can be tuned by changing the tube length [86