Analysis of self-heating of thermally assisted spin-transfer torque magnetic random access memory

• Austin Deschenes,
• Sadid Muneer,
• Mustafa Akbulut,
• Ali Gokirmak and
• Helena Silva

Beilstein J. Nanotechnol. 2016, 7, 1676–1683, doi:10.3762/bjnano.7.160

• T is the local temperature. Temperature-dependent materials properties [7][10][11][12][13][14] (Figure 3) are used for CoFeB, MgO, and Fe. The temperature-dependent thermal conductivity of CoFeB is calculated using the Wiedemann–Franz law: where L is the Lorenz number. It is assumed the annealing

• temperature was sufficiently low so as to not cause crystallization [7] on the MgO–CoFeB interface, leaving the CoFeB completely amorphous. The Pd–Co layers are treated as an alloy due to the large number of sub-nanometer thick layers. The temperature-dependent materials properties of the PdCo alloy were

• ) and reduced distance to the thermal boundary for heat generated on the bottom of the MTJ. Assuming constant resistances for the two states – which is equivalent to assuming switching occurs only at the end of the pulses – together with temperature-dependent changes of electrical and thermal

Microwave synthesis of high-quality and uniform 4 nm ZnFe₂O₄ nanocrystals for application in energy storage and nanomagnetics

• Christian Suchomski,
• Ben Breitung,
• Ralf Witte,
• Michael Knapp,
• Sondes Bauer,
• Tilo Baumbach,
• Christian Reitz and
• Torsten Brezesinski

Beilstein J. Nanotechnol. 2016, 7, 1350–1360, doi:10.3762/bjnano.7.126

• in Figure 4. It reveals a sextet pattern because of the presence of magnetic ordering. This is in accordance with both the magnetometry data below and temperature-dependent Mössbauer spectra shown in Supporting Information File 1, Figure S6. The low-temperature data can be fitted reasonably well with

Thermo-voltage measurements of atomic contacts at low temperature

• Ayelet Ofarim,
• Bastian Kopp,
• Thomas Möller,
• León Martin,
• Johannes Boneberg,
• Paul Leiderer and
• Elke Scheer

Beilstein J. Nanotechnol. 2016, 7, 767–775, doi:10.3762/bjnano.7.68

• from reduced lifetime, is largely facilitated. Furthermore, temperature-dependent effects of the transmission function that are expected in resonant tunneling situations can be revealed. Thus the ability to measure at variable temperature represents a considerable improvement compared to fixed

Magnetic switching of nanoscale antidot lattices

• Ulf Wiedwald,
• Joachim Gräfe,
• Kristof M. Lebecki,
• Maxim Skripnik,
• Felix Haering,
• Gisela Schütz,
• Paul Ziemann,
• Eberhard Goering and
• Ulrich Nowak

Beilstein J. Nanotechnol. 2016, 7, 733–750, doi:10.3762/bjnano.7.65

• material parameters and temperature dependent input functions. The latter are the exchange stiffness, the equilibrium magnetisation, and the parallel and perpendicular susceptibilities. The parallel susceptibility can be related to the uniaxial anisotropy [34][35]. In the past, these input functions were

Comparative kinematical analyses of Venus flytrap (Dionaea muscipula) snap traps

• Simon Poppinga,
• Tim Kampowski,
• Amélie Metzger,
• Olga Speck and
• Thomas Speck

Beilstein J. Nanotechnol. 2016, 7, 664–674, doi:10.3762/bjnano.7.59

• motion is ultimately dictated by the flow of interstitial water through the lobes, future comparative snapping experiments should be performed in temperature-constant chambers to exclude even small temperature-dependent physiological differences. As a conclusion it can be said that the Venus flytrap has

Plasticity-mediated collapse and recrystallization in hollow copper nanowires: a molecular dynamics simulation

• Amlan Dutta,
• Arup Kumar Raychaudhuri and
• Tanusri Saha-Dasgupta

Beilstein J. Nanotechnol. 2016, 7, 228–235, doi:10.3762/bjnano.7.21

• ), 700 K (red) and 750 K (blue) in the high temperature regime. The temperature-dependent trend is found to be generally different in the two regimes. The insets offer a closer look during the first few picoseconds of the simulations. Interestingly, in this short timescale, the trends are found to be

Single-molecule magnet behavior in 2,2’-bipyrimidine-bridged dilanthanide complexes

• Wen Yu,
• Frank Schramm,
• Eufemio Moreno Pineda,
• Yanhua Lan,
• Olaf Fuhr,
• Jinjie Chen,
• Hironari Isshiki,
• Wolfgang Wernsdorfer,
• Wulf Wulfhekel and
• Mario Ruben

Beilstein J. Nanotechnol. 2016, 7, 126–137, doi:10.3762/bjnano.7.15

• of 2–20 K and the frequency range of 0.1–1500 Hz with and without applied DC field. No SMM behavior was observed in compound 4 with or without an applied DC field. On the contrary, compound 3 shows a clear temperature dependent in-phase (χ'M(T)) and out of phase (χ"M(T)) component under zero field

Plasma fluorination of vertically aligned carbon nanotubes: functionalization and thermal stability

• Claudia Struzzi,
• Mattia Scardamaglia,
• Axel Hemberg,
• Luca Petaccia,
• Jean-François Colomer,
• Rony Snyders and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2015, 6, 2263–2271, doi:10.3762/bjnano.6.232

• the vCNTs. A temperature-dependent study was performed and the resulting defluorination process is discussed based on the analysis carried out using different techniques such as XPS, ultraviolet photoemission spectroscopy (UPS) and Raman spectroscopy. We observed that oxygen present in the plasma

• the BaDElPh beamline of the Elettra synchrotron in Trieste, Italy [21]. A temperature-dependent study was performed by thermal heating in ultrahigh vacuum: the selected temperature was reached in about 20 min, and the sample was kept for 15 min at that temperature before turning off the heating. The

• . Temperature-dependent XPS analysis of functionalized vCNTs. (a) C 1s spectra acquired as a function of heating temperature. The C 1s spectrum recorded just after the fluorination is labelled RT, the pristine spectrum is the bottom curve. The spectra were normalized and stacked for better visualization of

Paramagnetism of cobalt-doped ZnO nanoparticles obtained by microwave solvothermal synthesis

• Jacek Wojnarowicz,
• Sylwia Kusnieruk,
• Tadeusz Chudoba,
• Stanislaw Gierlotka,
• Witold Lojkowski,
• Wojciech Knoff,
• Malgorzata I. Lukasiewicz,
• Bartlomiej S. Witkowski,
• Anna Wolska,
• Marcin T. Klepka,
• Tomasz Story and
• Marek Godlewski

Beilstein J. Nanotechnol. 2015, 6, 1957–1969, doi:10.3762/bjnano.6.200

• (Figure 13c). The reciprocal magnetic susceptibility is only weakly temperature dependent for T > 20 K (Figure 13c) and then at low temperature, it drops rapidly to zero at T > 0 K. For this material, the XRD investigation shows formation of metallic inclusions. Thus, we assume that the situation closely

Temperature-dependent breakdown of hydrogen peroxide-treated ZnO and TiO₂ nanoparticle agglomerates

• Sinan Sabuncu and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 1897–1903, doi:10.3762/bjnano.6.193

• surface of the NPs [11][12][13][14][15]. Another external factor, temperature, can be utilized for this purpose. In this respect, in several studies, the temperature-dependent viscosity of nanofluids (which could be defined as solid–liquid materials established by the NP dispersions in the range of 1–100

• shown in Figure 4b. The broadened bands in the spectra after H2O2 treatment suggest that the grain size was reduced. Temperature-dependent size distribution of hydroxylated NPs The TiO2 and ZnO NPs used in the study are poorly dispersed in dH2O. When suspensions of these NPs are prepared, large clusters

• the hydrodynamic radius of the NPs in their suspension in water. Figure 4 shows the temperature-dependent, hydrodynamic radius change of the untreated and hydroxylated TiO2 NPs. As mentioned above, the hydroxylation process removes possible impurities from the NP surface and increases the density of

Thermal energy storage – overview and specific insight into nitrate salts for sensible and latent heat storage

• Nicole Pfleger,
• Thomas Bauer,
• Claudia Martin,
• Markus Eck and
• Antje Wörner

Beilstein J. Nanotechnol. 2015, 6, 1487–1497, doi:10.3762/bjnano.6.154

• turbines to produce electricity. Because the heat is generated at a specific and constant temperature and because of the temperature dependent water to steam transition the pressure of the steam can be adjusted to a level which is required by the turbine. Besides the melting temperature another important

• density there are consistent data from the literature in the liquid range. Also the density of multicomponent nitrate mixtures consisting of Ca(NO3)2, KNO3, LiNO3 and NaNO3 has been investigated [15]. It was shown that the temperature dependent molar volume can be estimated by a linear volumetric

• . Because the radius is increasing with the period (rows) of the periodic table the stability increases within the group of the periodic table. Thermal stabilities can be described by the temperature dependent equilibrium constant of decomposition reactions. Temperature dependent values are given for

Current–voltage characteristics of manganite–titanite perovskite junctions

• Benedikt Ifland,
• Patrick Peretzki,
• Birte Kressdorf,
• Philipp Saring,
• Andreas Kelling,
• Michael Seibt and
• Christian Jooss

Beilstein J. Nanotechnol. 2015, 6, 1467–1484, doi:10.3762/bjnano.6.152

• colossal electro-resistance (CER). For the perovskite heterojunction La0.32Pr0.33Ca0.33MnO3 with 0.5 wt % Nb-doped SrTiO3, the influence of a magnetic field on the temperature-dependent photovoltaic effect was reported [5]. In contrast, STNO has a band gap of around Eg = 3.2 eV [25] and the reported type

• range, which consequently reduces a typical device thickness [2]. For perovskite oxides, no direct measurement of the diffusion length has been reported so far. From the experimental viewpoint, one of the main tools to study photovoltaic devices is the temperature-dependent analysis of current–voltage

• and acceptors in the conduction or valence band is given by nD and nA, respectively. Since the temperature dependence of the intrinsic charge carrier density, ni, is given by the saturation current is also temperature dependent where NC and NV are the effective densities of states of the conduction

Electron-stimulated purification of platinum nanostructures grown via focused electron beam induced deposition

• Brett B. Lewis,
• Michael G. Stanford,
• Jason D. Fowlkes,
• Kevin Lester,
• Harald Plank and
• Philip D. Rack

Beilstein J. Nanotechnol. 2015, 6, 907–918, doi:10.3762/bjnano.6.94

• the resultant percolating network and ultimately their temperature dependent electrical behavior which can reveal the granular properties of the evolving nanostructure as well as the insulator to metal transition. Modeling Finally, to emulate the purification reaction we have developed a model which

Manganese oxide phases and morphologies: A study on calcination temperature and atmospheric dependence

• Matthias Augustin,
• Daniela Fenske,
• Ingo Bardenhagen,
• Anne Westphal,
• Martin Knipper,
• Thorsten Plaggenborg,
• Joanna Kolny-Olesiak and
• Jürgen Parisi

Beilstein J. Nanotechnol. 2015, 6, 47–59, doi:10.3762/bjnano.6.6

• the different manganese oxides via one route facilitates assigning actual structure–property relationships. The oxidation process related to the different MnOx species was observed by in situ X-ray diffraction (XRD) measurements showing time- and temperature-dependent phase transformations occurring

• situ XRD measurements showed the sequence of time- and temperature-dependent phase transformations during oxidation of the Mn(II) glycolate precursor to α-Mn2O3 via Mn3O4 and Mn5O8 in O2 atmosphere. Structural and morphological investigations revealed the dependence of the lattice constants and

Influence of the supramolecular architecture on the magnetic properties of a Dy^III single-molecule magnet: an ab initio investigation

• Julie Jung,
• Olivier Cador,
• Kevin Bernot,
• Fabrice Pointillart,
• Javier Luzon and
• Boris Le Guennic

Beilstein J. Nanotechnol. 2014, 5, 2267–2274, doi:10.3762/bjnano.5.236

• energies of the ground multiplet (6H15/2) of the Dy ion. The anisotropy tensor, the energy of the eight Kramer doublets of the ground spin–orbit state, as well as the temperature-dependent magnetic susceptibility and the molar magnetization at 2 K were computed to support experimental results. Atomic

Silicon and germanium nanocrystals: properties and characterization

• Ivana Capan,
• Alexandra Carvalho and
• José Coutinho

Beilstein J. Nanotechnol. 2014, 5, 1787–1794, doi:10.3762/bjnano.5.189

• simple MOS structure, with Ge NCs embedded in the SiO2 film deposited on a Si substrate. In order to check for the existence of the deep level traps coming from the Si/SiO2 interface, temperature dependent C–V measurements have been performed. The activation energy of the electron emission has been

The influence of molecular mobility on the properties of networks of gold nanoparticles and organic ligands

• Edwin J. Devid,
• Paulo N. Martinho,
• M. Venkata Kamalakar,
• Úna Prendergast,
• Christian Kübel,
• Tibebe Lemma,
• Jean-François Dayen,
• Tia. E. Keyes,
• Bernard Doudin,
• Mario Ruben and
• Sense Jan van der Molen

Beilstein J. Nanotechnol. 2014, 5, 1664–1674, doi:10.3762/bjnano.5.177

• ) provides insight into the selectivity of the bond formation. Remarkably, Raman experiments also reveal subtle shifts in some S-BPP modes related to reversible structural modification within the array induced by temperature. This observation is compared to temperature-dependent transport experiments. For

• the nanoparticles preferably through the thiol linker. Temperature-dependent Raman spectroscopy on 2D Au-NP–S-BPP arrays The studies by Raman microscopy over the temperature range 80 to 353 K are shown in Figure 4. The absence of significant chemical changes with temperature is indicated by the

• them sensitive to electronic changes within their molecular vicinity, particularly in conjugated systems [40][41]. The surface-bound benzenethiol is sensitive to temperature, but the alkyne exhibits much larger temperature-dependent spectral changes, with a shift of 16 cm−1 between 80 and 353 K. We

Current state of laser synthesis of metal and alloy nanoparticles as ligand-free reference materials for nano-toxicological assays

• Christoph Rehbock,
• Jurij Jakobi,
• Lisa Gamrad,
• Selina van der Meer,
• Daniela Tiedemann,
• Ulrike Taylor,
• Wilfried Kues,
• Detlef Rath and
• Stephan Barcikowski

Beilstein J. Nanotechnol. 2014, 5, 1523–1541, doi:10.3762/bjnano.5.165

• unique electrostatically controlled nano-environment allows observations of gold nanoparticle buffering effects and specific ion adsorption which cannot be studied in ligand-stabilized systems [45]. Furthermore, it should be noted that the Debeye parameter is known to be temperature-dependent as well (κ

Review of nanostructured devices for thermoelectric applications

• Giovanni Pennelli

Beilstein J. Nanotechnol. 2014, 5, 1268–1284, doi:10.3762/bjnano.5.141

• temperature dependent. Furthermore, these parameters depend on the temperature through non-linear relationships, that in general can be determined only by experimental measurements. Therefore, a numerical solution of the thermoelectric equations (Equation 5 and Equation 6), which takes in account the

Biocalcite, a multifunctional inorganic polymer: Building block for calcareous sponge spicules and bioseed for the synthesis of calcium phosphate-based bone

• Xiaohong Wang,
• Heinz C. Schröder and
• Werner E. G. Müller

Beilstein J. Nanotechnol. 2014, 5, 610–621, doi:10.3762/bjnano.5.72

• for the round-shaped vaterite deposits is 9.95 ± 1.60. The enzyme-mediated deposition of calcium carbonate is markedly temperature dependent [31]. While at 10 °C the reaction velocity of calcium carbonate deposition is almost identical in the enzyme-containing and enzyme-lacking assays, at higher

Impact of thermal frequency drift on highest precision force microscopy using quartz-based force sensors at low temperatures

• Florian Pielmeier,
• Daniel Meuer,
• Daniel Schmid,
• Christoph Strunk and
• Franz J. Giessibl

Beilstein J. Nanotechnol. 2014, 5, 407–412, doi:10.3762/bjnano.5.48

• and the qPlus sensors (Figure 3a) and the LER (Figure 3b). Again, the wiggles in the curves for the qPlus sensors are caused by external excitations due to a lacking damping system. The kink around 13 K from Figure 2 shows up as a clear step. In temperature dependent measurements it might therefore be

Large-scale atomistic and quantum-mechanical simulations of a Nafion membrane: Morphology, proton solvation and charge transport

• Pavel V. Komarov,
• Pavel G. Khalatur and
• Alexei R. Khokhlov

Beilstein J. Nanotechnol. 2013, 4, 567–587, doi:10.3762/bjnano.4.65

• this effect might occur because more entropy is available to ion pairs than to dissociated ions, leading to an entropically driven temperature dependent contribution to the binding free energy. For the ionomeric system studied here we observe an opposite effect of the temperature, the ion pairing

The role of electron-stimulated desorption in focused electron beam induced deposition

• Willem F. van Dorp,
• Thomas W. Hansen,
• Jakob B. Wagner and
• Jeff T. M. De Hosson

Beilstein J. Nanotechnol. 2013, 4, 474–480, doi:10.3762/bjnano.4.56

• concentration gradient. The last two terms describe dissociation by the electron beam and desorption from the substrate to the gas phase. The growth rate, R (cm·s−1), can be defined as: with Vmolecule (cm3) being the volume of a deposited molecule. Equation 1 has two temperature-dependent terms: diffusion and

Structural and thermoelectric properties of TMGa₃ (TM = Fe, Co) thin films

• Sebastian Schnurr,
• Ulf Wiedwald,
• Paul Ziemann,
• Valeriy Y. Verchenko and
• Andrei V. Shevelkov

Beilstein J. Nanotechnol. 2013, 4, 461–466, doi:10.3762/bjnano.4.54

• Seebeck coefficients To determine the temperature-dependent Seebeck coefficients S(T) of (TM)Ga3 films, in a first step the films were complemented by strips of Pb to form (TM)Ga3/Pb-thermocouples arranged on a thin (140 μm) glass substrate. Since S(T) values for Pb are well documented in the literature

Antiferromagnetic coupling of TbPc₂ molecules to ultrathin Ni and Co films

• David Klar,
• Svetlana Klyatskaya,
• Andrea Candini,
• Bernhard Krumme,
• Kurt Kummer,
• Philippe Ohresser,
• Valdis Corradini,
• Valentina de Renzi,
• Roberto Biagi,
• Loic Joly,
• Jean-Paul Kappler,
• Umberto del Pennino,
• Marco Affronte,
• Heiko Wende and
• Mario Ruben

Beilstein J. Nanotechnol. 2013, 4, 320–324, doi:10.3762/bjnano.4.36

• demonstration of an antiferromagnetic coupling of rare-earth–Pc2 molecules to ferromagnetic substrates. The quantitative analysis of the antiferromagnetic coupling strength goes beyond the scope of this manuscript. This can be achieved by experimental investigation by means of a detailed temperature-dependent