journal

# Journal of Physics. Condensed Matter: An Institute of Physics Journal

journal
#1
Qianhui Mao, Bin Chen, Jinhu Yang, Yannan Zhang, Hangdong Wang, Minghu Fang
We have investigated the critical behavior of Fe$_{2.85}$GeTe$_2$ single crystals near the paramagnetic-ferromagnetic transition by bulk dc magnetization measurements. The critical exponents $\beta$, $\gamma$ and $\delta$, obtained from modified Arrott plot, Kouvel-Fisher method, and critical isothermal magnetization analysis, could fulfill the Widom scaling law. The self-consistency and reliability of these exponents are further verified by the magnetic state equations below and above the Curie temperature at high magnetic field...
July 18, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#2
Julen Ibanez, Manuel Dos Santos Dias, Stefan Bluegel, Samir Lounis
Single adatoms offer an exceptional playground for studying magnetism and its associated dynamics at the atomic scale.&#13; Here we review recent results on single adatoms deposited on metallic substrates, based on time-dependent density functional theory.&#13; First we analyze quantum zero-point spin-fluctuations (ZPSF) as calculated from the fluctuation-dissipation theorem, and show how they affect the magnetic stability by modifying the magnetic anisotropy energy.&#13; We also assess the impact of ZPSF in the limit of small hybridization to the substrate characteristic of semi-insulating substrates, connecting to recent experimental investigations where magnetic stability of a single adatom was achieved for the first time...
July 18, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#3
Hewen Wang, Musheng Wu, Zhengfang Tian, Gang Liu, Bo Xu, Shengyuan A Yang, Chuying Ouyang
It was reported by Hu et al. [ACS Appl. Mater. Interfaces 2015, 7, 24016] that Li adsorption on the Ca2N monolayer is energetically unfavorable, although it was found to be a good candidate for Na storage. In this paper, from first-principles calculations, it is shown that compressive stain can greatly enhance the interactions between Li adsorbate and the Ca2N host, which is beneficial to prevent Li from clustering on the surface and thus Li storage becomes possible. Charge distribution analysis further shows that the enhanced Li-adsorption is a result of the increased surface charge density and the more confined charge distribution under compressive strain...
July 18, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#4
Svitlana Stelmakh, Kazimierz Skrobas, Stanislaw Gierlotka, Bogdan Palosz
A new methodology of performing structural analysis of nanocrystals based on wide angle powder diffraction is proposed. It combines Molecular Dynamics simulations with the analysis of Pair Distribution Function. The actual analysis was performed on CdSe quantum dots. MD simulations of nanocrystals with shapes defined by low-index atomic planes, (100), (110), and (111) introduced bulk and surface relaxation in initially perfect crystal lattice. In search for the best atomistic model of the actual CdSe nanocrystals, experimental structure functions S(Q) and interatomic distance functions G(r) were matched to those calculated with MD models...
July 18, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#5
Shuvojit Paul, Basudev Roy, Ayan Banerjee
We linearize the Stokes-Oldroyd B Model for small perturbations and instantaneous hydrodynamic friction to simulate the environment for a free and confined Brownian particle. We use the standard Green's function approach to determine the viscoelasticity, and show that the expression obtained for the frequency dependent viscosity is similar to that given by the Jeffrey's model, though the latter describes viscoelasticity by the bulk storage and loss moduli that is represented by a complex elastic modulus G(ω) of the fluid concerned...
July 18, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#6
Yury A Budkov
We present a nonlocal statistical field theory of a dilute electrolyte solution with small additive of dipolar particles. We postulate that every dipolar particle is associated with an arbitrary probability distribution function (PDF) of distance between its charge centers. Using the standard Hubbard-Stratonovich transformation, we represent the configuration integral of the system in the functional integral form. We show that in the limit of a small permanent dipole moment, the functional in integrand exponent takes the well known form of the Poisson-Boltzmann-Langevin (PBL) functional...
July 17, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#7
Yumei Zhou, Yu Wang, Dezhen Xue, Xiangdong Ding, Jun Sun, Xiaobing Ren, T Lookman
The alloy Ti50(Pd40Cr10) undergoes a strain glass transition around room temperature evidenced by frequency dispersion of dynamic mechanical properties and lack of average structure change from that of the high symmetry austenite phase. However, since the strain glass transition is not a thermodynamic phase transition but a dynamic freezing process governed by the kinetics, a quantitative characterization of the slowing down of dynamics during the strain glass transition is still lacking. In the present study, the probability distribution function (PDF) of the relaxation time of the strain glass alloy is investigated spanning the whole transition temperature range (253 K -313 K)...
July 17, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#8
Suman Kamboj, Shekhar Das, Anshu Sirohi, Rajeswari Roy Chowdhury, Sirshendu Gayen, Vishal Maurya, S Patnaik, Goutam Sheet
The surface states of topological insulators (TI) are protected by time reversal symmetry and they display intrinsic spin helicity where the momentum of the charge carriers decides their spin states. As a consequence, a current injected through the surface states becomes spin polarized and this transport spin-polarization leads to a proportionate suppression of Andreev reflection in superconductor/TI junctions. Here we show that upon doping Bi$_2$Se$_3$ with Mn, the transport spin-polarization is seen to be monotonically suppressed...
July 17, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#9
Cai Xiaoming
Using exact numerical methods, we study the interplay between p-wave superconductivity and off-diagonal modulation in the incommensurate off-diagonal Aubry-André model with p-wave pairing. When chemical potential is zero, the modulation not only leads to an Anderson-like localization with all bulk states changing into critical ones, but also induces a topological phase transition accompanying the disappearing of exponentially localized zero-energy edge Majorana fermions. These two transitions happen at different places and true Anderson localization is absent...
July 17, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#10
Ferran Jovell, Xavier Cartoixà
We study the ballistic transmission and the contact resistance (R c ) of a graphite-graphene contact in a top contact geometry from first principles. We find that the calculated R c 's depend on the amount of graphene-graphite overlap, but quickly saturate for transfer lengths of the order of a few tens of Å. For contacts overlapping more than this transfer length, the R c can be lower than the 100 [Formula: see text] mark. On the other hand, edge graphite-graphene contacts are expected to have very low contact resistance...
July 17, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#11
Konstantin Arutyunov, Sergey A Chernyaev, Tair Karabasov, Vasiliy Stolyarov, Andrey Vasenko
Rapid development of micro- and nanofabrication methods have provoked interest and enabled experimental&#13; studies of electronic properties of a vast class of (sub)micrometer-size solid state systems. Mesoscopic-size&#13; hybrid structures, containing superconducting elements, have become interesting objects for basic research&#13; studies and various applications, ranging from medical and astrophysical sensors to quantum computing.&#13; One of the most important aspects of physics, governing the behavior of such systems, is the finite&#13; concentration of nonequilibrium quasiparticles, present in a superconductor even well below the temperature&#13; of superconducting transition...
July 17, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#12
P Kumar, Christopher Wagner
We present a model to probe metamagnetic properties in systems with a variable number of interacting spins. Thermodynamic properties such as the magnetization per particle &lt;i&gt;m&lt;/i&gt;(&lt;i&gt;B, T, N&lt;/i&gt;), linear susceptibility χ&lt;sub&gt;1&lt;/sub&gt; (&lt;i&gt;T&lt;/i&gt;), and nonlinear susceptibilities χ&lt;sub&gt;3&lt;/sub&gt; (&lt;i&gt;T&lt;/i&gt;) and χ&lt;sub&gt;5&lt;/sub&gt; (&lt;i&gt;T&lt;/i&gt;) were calculated...
July 17, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#13
Zhiguo Geng, Yu Gui Peng, Ya Xi Shen, Degang Zhao, Xuefeng Zhu
In this work, we investigate comprehensively the unidirectional transport of sound in coupled cavities of a modified honeycomb lattice. The results clearly show that a pair of topological states carrying opposite pseudospins can be constructed at the edge of truncated lattices of non-trivial band gaps, which is different from previous schemes that topological states with opposite pseudospins were constructed at the interface of modified honeycomb lattices of trivial and non-trivial band gaps. Our work paves the way to exploring unidirectional edge transport of sound with topological protection in closed systems that are beneficial in large-scale device integration and low-loss operation...
July 16, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#14
YongJun Zhang, Xinbei Xia, Wenbing Jiang, YunFeng Wang, Jiyong Liu, Huiqiu Yuan, Hanoh Lee
We have synthesized high quality single crystals of Sm&lt;sub&gt;4&lt;/sub&gt;Co&lt;sub&gt;3&lt;/sub&gt;Ga&lt;sub&gt;16&lt;/sub&gt; with Galium flux and investigated its physical properties with transport, magnetization and specific-heat measurements. Antiferromagnetic transition below 6.7K has been detected. No superconducting transition have been dectected down to 0.5K from our single crystals. Based on our experimental result, Sm&lt;sup&gt;3+&lt;/sup&gt; state in Sm&lt;sub&gt;4&lt;/sub&gt;Co&lt;sub&gt;3&lt;/sub&gt;Ga&lt;sub&gt;16&lt;/sub&gt; is likely well localized, in which stable magnetic moment in its doubly degenerated ground state contributes to the magnetic order with little interference of Kondo type of interaction...
July 16, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#15
Marcelo Antonio Pavanello, Renan Trevisoli, Rodrigo Trevisoli Doria, Michelly de Souza
This paper presents a compact analytical model for the static and dynamic electrical characteristics of Junctionless Nanowire Transistors. The static drain current model formulation is derived from the two-dimensional solution of the Poisson equation with appropriate boundary conditions and long-channel devices, leading to a continuous effective surface potential that accounts for the conduction in partial depletion and accumulation regimes. The long-channel model is modified to account for short-channel effects by using the coupled solution of three-dimensional Laplace equation with the two-dimensional Poisson equation...
July 13, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#16
Hongcheng Lian, Le Hua Qi, Jun Luo, Kewen Hu
Uniform graphene films and micro-patterns are the cornerstones of graphene-based printed electronics. However, disk-like reduced graphene oxide (RGO) sheets trend to concentrate at the edge of the drop because of the famous coffee-ring effect, resulting in non-uniform patterns. To understand the physics of coffee-ring formation for RGO droplets on hydrophilic substrates, we propose a mechanical model to elucidate the influence and its mechanism of substrate wettability on the solute migration behavior and solute distribution morphology of RGO droplets...
July 13, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#17
Boris Ya Shapiro, Irina Shapiro, Dingping Li, Baruch Rosenstein
Superconductivity of the second kind was observed in many 3D Weyl and Dirac&#13; semi-metals while in the $PdTe_{2}$, superconductivity is clearly of the&#13; first kind. This is very rare in Dirac semi - metals, but is expected in&#13; clean conventional metallic superconductors with 3D parabolic dispersion&#13; relation. The conduction bands in this material exhibit the linear (Dirac)&#13; dispersion only along two directions, while in the third direction the&#13; dispersion is parabolic...
July 12, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#18
Xiaoqing Liang, Xiangyu Kong, Sheng-Jie Lu, Yingying Huang, Jijun Zhao, Hong-Guang Xu, Weijun Zheng, Xiao Cheng Zeng
The structural, electronic and magnetic properties of dual Cr atoms doped germanium anionic clusters, Cr&lt;sub&gt;2&lt;/sub&gt;Ge&lt;sub&gt;n&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt; (n = 3-14), have been investigated by using photoelectron spectroscopy in combination with density-functional theory (DFT) calculations. The low-lying structures of Cr&lt;sub&gt;2&lt;/sub&gt;Ge&lt;sub&gt;n&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt; are determined by DFT based genetic algorithm optimization...
July 11, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#19
Richa Bhargava, Shakeel Khan
In this report, Cu2O and Cu2O/rGO nanocomposites were successfully synthesized through chemical reduction method using glucose as a reducing agent for Graphene Oxide (GO). The structural properties of the as-prepared samples were studied by using X-ray diffraction (XRD), which shows that the synthesized samples have cubic phase. The field scanning electron microscopy (FESEM) results reveal that the Cu2O nanoparticles having spherical structures are grown on the wrinkled graphene sheets. The presence of different bondings and the functional groups of the as-synthesized sample were analyzed by Fourier transform infrared spectroscopy (FTIR)...
July 11, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
#20
E C Blomberg, M A Tanatar, A Thaler, S L Bud'ko, P C Canfield, R Prozorov
In-plane resistivity anisotropy was measured in strain-detwinned as-grown and partially annealed samples of isovalently-substituted [Formula: see text] ([Formula: see text]) and the results were contrasted with previous reports on anneal samples with low residual resistivity. In samples with high residual resistivity, detwinned with application of strain, the difference of the two components of in-plane resistivity in the orthorhombic phase, [Formula: see text], was found to obey Matthiessen rule irrespective of sample composition, which is in stark contrast with observations on annealed samples...
July 11, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
journal
journal
40367
1
2
Fetch more papers »
Fetching more papers...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.

### Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign