TRANSPORT AND MAGNETIC PROPERTIES OF Bi BASED MULTIPHASE SUPERCONDUCTORS

1999 ◽  
Vol 13 (29n31) ◽  
pp. 3741-3743 ◽  
Author(s):  
P. Vašek ◽  
I. Janeček

A series of (Bi,Pb)SrCuCaO samples with varying volume fraction of the 2223 phase (determined by X-ray diffraction) has been prepared. Temperature dependence of the resistance, Hall effect and magnetic susceptibility has been measured. Neither susceptibility (both dc and ac) nor electrical resistivity in magnetic field reveal the presence of the low temperature (2212) phase. On the other hand the Hall voltage in the mixed state is very sensitive to the presence of different phases. Obtained results have been discussed within the frame of the effective medium approach and related to the growth mechanism of the 2223 phase.

2004 ◽  
Vol 848 ◽  
Author(s):  
Evan Lyle Thomas ◽  
Erin E. Erickson ◽  
Monica Moldovan ◽  
David P. Young ◽  
Julia Y. Chan

AbstractA new member of the LnMIn5 family, ErCoIn5, has been synthesized by a flux-growth method. The structure of ErCoIn5 was determined by single crystal X-ray diffraction. It crystallizes in the tetragonal space group P4/mmm, Z = 1, with lattice parameters a = 4.5400(4) and c = 7.3970(7) Å, and V = 152.46(2) Å3. Electrical resistivity data show metallic behavior. Magnetic susceptibility measurements show this compound to be antiferromagnetic with TN = 5.1 K. We compare these experimental results with those of LaCoIn5 in an effort to better understand the effect of the structural trends observed on the transport and magnetic properties.


2007 ◽  
Vol 26-28 ◽  
pp. 563-565
Author(s):  
Kazuhiko Iwai ◽  
Manabu Usui ◽  
Shigeo Asai

A static magnetic field and an alternating current are imposed on a metallic alloy during solidification for a crystal alignment of the primary phase. A Sn-10%Pb is selected as a sample because its primary phase is expected to have an anisotropic nature in magnetic susceptibility. In the x-ray diffraction pattern of the sample solidified without the magnetic field, the first and second highest peaks are (101) and (211) planes. On the other hand, those solidified with the magnetic field are (200) and (220) planes which are magnetically preferred planes. That is, the primary phase crystals in the sample solidified with the magnetic field are aligned to the specific direction.


2016 ◽  
Vol 257 ◽  
pp. 107-110 ◽  
Author(s):  
Tadeusz Groń ◽  
Elzbieta Tomaszewicz ◽  
Marek Berkowski ◽  
Monika Oboz ◽  
Joachim Kusz ◽  
...  

X-ray diffraction measurement at 298 K of CdMoO4:Dy3+ showed that the molybdenum ions are tetrahedral coordinated and Cd/Dy – dodecahedral coordinated. The Dy3+ ions are randomly distributed in the unit cell, substituting the Cd2+ ones. The temperature dependence of ac and dc magnetic susceptibility showed a lack of the Curie-Weiss behaviour and a weak response to the magnetic field. The magnetization isotherms, M(H), showed a paramagnetic-diamagnetic transition at 17 K for 〈100〉 direction and at 35 K for 〈001〉 one in the magnetic field of 70 kOe. As the temperature increased this transition was moving toward smaller magnetic fields.


1994 ◽  
Vol 08 (19) ◽  
pp. 1175-1183 ◽  
Author(s):  
G. RAVI CHANDRA ◽  
B. GOPALA KRISHNA ◽  
S. V. SURYANARAYANA ◽  
T. S. N. MURTHY

The effect of the addition of Sn on the superconducting properties of the Bi 1.7 Pb 0.3 Sr 2 Ca 2 Cu 3 O y system as functions of Sn concentration and heat treatment has been studied by dc electrical resistance, ac magnetic susceptibility, and X-ray diffraction. Tin addition suppresses the volume fraction of the high T c phase. Samples with Sn > 0.1 show metallic behavior up to LNT. The formation of the Ca 2 PbO 4 phase is promoted by Sn. This depletes the amount of Pb and Ca necessary for the formation of the 2223 phase, thus reducing the volume fraction of the 2223 phase. It is possible that at least a small fraction of tin substitutes some of the cationic sites of the starting composition. The results of the different measurements are presented.


DYNA ◽  
2019 ◽  
Vol 86 (211) ◽  
pp. 278-287
Author(s):  
Javier Alberto Olarte Torres ◽  
María Cristina Cifuentes Arcila ◽  
Harvey Andrés Suárez Moreno

This paper presents the results obtained from the synthesis and morphological characterization of different magnetite samples:  La0.67-x Prx Ca0.33 MnO3.LaMn1-x Cox O3 and LaMn1-x Nix O3 at 0.13 ≤ 𝑥𝑥 ≤ 0.67 produced by a solid-state reaction mechanism and 𝐿𝐿𝐿𝐿𝑀𝑀𝑀𝑀1−𝑥𝑥(𝐶𝐶𝐶𝐶/𝑁𝑁𝑁𝑁)𝑥𝑥𝑂𝑂3 at 0.0 ≤ 𝑥𝑥 ≤ 0.5 produced by the sol-gel method. These samples were characterized using X-ray diffraction spectroscopy and by measuring electric resistivity and magnetic susceptibility which were carried out as a function of temperature. Notably, the effects of strain and compressive strength on the lattices of magnetite samples were highly dependent on the concentration of 𝑃𝑃𝑟𝑟, 𝐶𝐶𝐶𝐶, and 𝑁𝑁𝑁𝑁. Moreover, the transition temperatures of metal-insulator and ferromagnetic-paramagnetic phases also largely depend on these strength effects, e.g., at higher concentrations of 𝑃𝑃𝑟𝑟, effects of increased strain strength were observed, relocating the shifts of ferromagnetic-paramagnetic transitions to lower temperatures. On the other hand, effects of increased compressive strength were observed at higher concentrations of 𝑁𝑁𝑁𝑁 and 𝐶𝐶𝐶𝐶, relocating the shifts of ferromagnetic-paramagnetic and metal-insulator transitions to higher temperatures.


1987 ◽  
Vol 99 ◽  
Author(s):  
R. S. Liu ◽  
G. C. Lin ◽  
H. M. Sung ◽  
Y. C. Chen ◽  
O. C. C. Lin

ABSTRACTLa-Ba-Cu-O and Y-Ba-Cu-O superconducting systems have been successfully prepared by gel techniques with high degree of chemical homogeneity. The precursor gel was synthesized from mixture of the corresponding metallic nitrates and di-carboxylic acids. The sintered oxides prepared from the different dicarboxylic acids were all Tc = 90K perovskite superconductors. However differences in electrical and magnetic properties were also observed. Effects due to the different acids elucidated by magnetic susceptibility measurements and X-ray diffraction analysis will be discussed.


1996 ◽  
Vol 453 ◽  
Author(s):  
H.-C. Zur Loye ◽  
P. Núñez ◽  
M. A. Rzeznik

AbstractThe one-dimensional compounds Sr3MgPtO6, Sr3MgIrO6, Sr3MgRhO6, Sr3GdRhO6, have been synthesized and structurally characterized by Rietveld refinement of powder X-ray diffraction data. All four compounds are isostructural with the rhombohedral K4CdCl6-type structure. The structure consists of infinite one-dimensional chains of alternating face-shared MO6 octahedra (M = Pt, Ir, Rh) and M′O6 (M′ = Gd, Mg) trigonal prisms. The strontium cations are located in a distorted square antiprismatic environment. Magnetic susceptibility data show that both Sr3MgIrO6 and Sr3MgRhO6 obey the Curie-Weiss law with θ = −6(1) K, and θ= −15(3)K, respectively. Sr3GdRhO6 obeys the Curie law with μeff = 7.80 B.M, consistent with an oxidation state of +3 for both rhodium and gadolinium.


1987 ◽  
Vol 01 (03n04) ◽  
pp. 989-992 ◽  
Author(s):  
M.T. Causa ◽  
S.M. Dutrús ◽  
C. Fainstein ◽  
G. Nieva ◽  
H.R. Salva ◽  
...  

We report here normal and superconducting properties of ABa 2 Cu 3 O 7−δ (with A=Y, Gd, Dy, and Er) and of Fe doped YBa2Cu3O7−δ . Results from X-ray powder diffraction, electrical resistivity, magnetic susceptibility, ESR, and specific heat measurements are presented, leading to a characterization of the magnetic properties of these materials. The effect of structural modifications of the lattice on the superconducting properties and the relative insensitivity of Tc to the presence of magnetic moments is discussed.


2009 ◽  
Vol 152-153 ◽  
pp. 79-84 ◽  
Author(s):  
Joan Josep Suñol ◽  
L. Escoda ◽  
C. García ◽  
V.M. Prida ◽  
Victor Vega ◽  
...  

Glass-coated Cu-Mn-Ga microwires were fabricated by Taylor-Ulitovsky technique. By means of energy dispersive spectroscopy microanalysis, an average alloy composition of Cu56Ga28Mn16 was determined. The temperature dependence of magnetization measured at a low magnetic field showed the coexistence of two ferromagnetic phases. The Curie temperature of one phase is 125 K and above room temperature for the other one. X-ray diffraction at room temperature and at 100 K reflects the presence of the same three crystalline phases corresponding to the cubic B2 Cu-Mn-Ga structure as a main phase and the minor phases of fcc Cu rich solid solution with Mn and Ga and the monoclinic CuO.


2014 ◽  
Vol 24 (3S1) ◽  
pp. 90-94 ◽  
Author(s):  
Le Tuan Tu ◽  
Luu Van Thiem ◽  
Pham Duc Thang

The magnetic properties in Co-Ni-P nanowires arrays with diameter of 200 nm were investigated. All the samples were prepared by electrodeposition method with pH of 5.5 and at room temperature. During the deposition, a magnetic field in range of 0 - 750 Oe was applied parallel to the wires axis. The crystalline structure and morphology of the samples were characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM), respectively. The hysteresis loops were measured at room temperature using vibrating sample magnetometry (VSM). The mixture of hcp phases of the Co-Ni-P based nanowires has been indicated by the XRD pattern. The obtained results show that with 750 Oe magnetic field applied during deposition we can obtain maximum coercivity value (2180 Oe). The \(M_{r}/M_{s}\) ratio was rapid increased when the magnetic field changed from 0 Oe to 750 Oe.


Sign in / Sign up

Export Citation Format

Share Document