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Showing papers on "Transition temperature published in 1995"


Journal ArticleDOI
01 Mar 1995-Nature
TL;DR: In this article, the phase of the order parameter is not important for determining the value of the transition temperature Tc and the change of many physical properties brought about by the transition, and the phase fluctuations, both classical and quantum, may have a significant influence on low-temperature properties.
Abstract: THE superconducting state of a metal is characterized by a complex order parameter with an amplitude and a phase In the BCS-Eliashberg mean-field theory1, which is a very good approximation for conventional metals, the phase of the order parameter is un-important for determining the value of the transition temperature Tc and the change of many physical properties brought about by the transition Here we argue that superconductors with low super-conducting carrier density (such as the organic and high-Tc oxide superconductors) are characterized by a relatively small phase 'stiffness9 and poor screening, both of which imply a significantly larger role for phase fluctuations As a consequence, in these mat-erials the transition to the superconducting state may not display typical mean-field behaviour, and phase fluctuations, both classical and quantum, may have a significant influence on low-temperature properties For some quasi-two-dimensional materials, notably underdoped high-temperature superconductors, the onset of long-range phase order controls the gross value of Tc as well as its systematic variation from one material to another

1,533 citations


Journal ArticleDOI
21 Apr 1995-Science
TL;DR: The high magnetic ordering temperatures of these cyano-bridged solids confirm that the incorporation of early transition elements into the lattice promotes stronger magnetic coupling by enhancing the backbonding into the cyanide π* orbitals.
Abstract: The molecular-based magnetic materials Cs 2 Mn || [V || (CN) 6 ] (1) and (Et 4 N) 0.5 Mn l.25 - [V(CN) 5 ]·2H 2 O ( 2 ) (where Et is ethyl) were prepared by the addition of manganese(II) triflate to aqueous solutions of the hexacyanovanadate(II) ion at 0°C. Whereas 1 crystallizes in a face-centered cubic lattice, 2 crystallizes in a noncubic space group. The cesium salt (1) has features characteristic of a three-dimensional ferrimagnet with a Neel transition at 125 kelvin. The tetraethylammonium salt (2) also behaves as a three-dimensional ferrimagnet with a Neel temperature of 230 kelvin; only two other molecular magnets have higher magnetic ordering temperatures. Saturation magnetization measurements indicate that in both compounds the V II and high-spin Mn II centers are antiferromagnetically coupled. Both 1 and 2 exhibit hysteresis loops characteristic of soft magnets below their magnetic phase-transition temperatures. The high magnetic ordering temperatures of these cyano-bridged solids confirm that the incorporation of early transition elements into the lattice promotes stronger magnetic coupling by enhancing the backbonding into the cyanide π* orbitals.

584 citations


Journal ArticleDOI
TL;DR: In this article, the influence of the processing parameters on the PTCR related properties is discussed, and special emphasis is placed on the phenomenon that the conductivity and grain size decrease with increasing donor concentration above ∼ 0.3 at%.
Abstract: Positive temperature coefficient of resistivity (PTCR) materials have become very important components, and among these materials barium titanate compounds make up the most important group. When properly processed these compounds show a high PTCR at the Curie temperature (the transition temperature from the ferroelectric tetragonal phase to the paraelectric cube phase). In the first half of this paper literature related to the resistivity-temperature behaviour is discussed. As explained by the well established Heywang model, the PTCR effect is caused by trapped electrons at the grain boundaries. From reviewing experimental results in the literature it is clear that the PTCR effect can not be explained by assuming only one kind of electron trap. It is concluded that as well as barium vacancies, adsorbed oxygen as 3d-elements can act as electron traps. In the second half of this paper, the influence of the processing parameters on the PTCR related properties is discussed. Special emphasis is placed on the phenomenon that the conductivity and grain size decrease abruptly with increasing donor concentration above ∼ 0.3 at%. Several models explaining this phenomenon are discussed and apparent discrepancies in experimental data are explained.

265 citations


Journal ArticleDOI
TL;DR: In this paper, the symmetric Ag pentagonal pinch mode of C60 using Raman spectroscopy was shown to have superconductivity at 40K using ac susceptibility measurements under hydrostatic conditions up to 15 kbar.

215 citations


Journal ArticleDOI
TL;DR: In this article, the thermodynamic and dynamic properties of several partially deuterated symmetric (equal block volume fraction) polyethylene-poly(ethylethylene) (PE-PEE), poly(methylene-propylene)-poly(ETHylethylon) (PEP) diblock copolymers were characterized above and below the order-disorder transition (ODT).
Abstract: The thermodynamic and dynamic properties of several partially deuterated symmetric (equal block volume fraction) polyethylene-poly(ethylethylene) (PE-PEE), poly(ethylene-propylene)-poly(ethylethylene) (PEP-PEE), and polyethylene-poly(ethylene-propylene) (PE-PEP) diblock copolymers were characterized above and below the order-disorder transition (ODT). A lamellar morphology was established for all temperatures below the ODT using small-angle neutron scattering (SANS) measurements with shear-aligned specimens. As T ODT is approached, the lamellar order weakens as evidenced by the loss of higher order SANS reflections and azimuthal smearing of the principal equitorial scattering peaks. SANS and rheology experiments also provided unambiguous evidence of composition fluctuations above the order-disorder transition temperature in each system. However, the temperature range of the fluctuations in the disordered state depends on the degree of polymerization, in accordance with fluctuation theory. A crossover in the disordered state between slightly and moderately stretched coils was also documented by SANS, coincident with the temperature where fluctuations become apparent rheologically.

186 citations


Journal ArticleDOI
TL;DR: In this paper, the authors used pulsed laser deposition to grow thin films of lanthanum-deficient LaxMnO3−δ (0.67≤x≤1) on (100) SrTiO3 substrates, which exhibit a ferromagnetic transition at temperatures ranging from 115 to 240 K with the transition temperature increasing with higher La deficiency.
Abstract: Epitaxial thin films of lanthanum‐deficient LaxMnO3−δ (0.67≤x≤1) have been grown on (100) SrTiO3 substrates by pulsed laser deposition. The as‐deposited films exhibit a ferromagnetic transition at temperatures ranging from 115 to 240 K, with the transition temperature (Tc) increasing with higher La deficiency. A sharp drop in resistivity and negative magnetoresistance is observed close to Tc, a behavior similar to that observed in divalent substituted La1−xMxMnO3−δ (M=Ba, Sr, Ca, Pb) films. Postannealing the films in O2 reduces the resistivity and raises the Tc to values close to room temperature. A magnetoresistance value of 130% (Δρ/ρH) has been obtained at 300 K at 4 T for a post‐annealed film with x=0.75.

161 citations


Journal ArticleDOI
TL;DR: In this article, the authors showed that the reliability of the predicted T ODT of a block copolymer depends on the accuracy of the expression for the Flory-Huggins interaction parameter X.
Abstract: Low molecular weight polystyrene-block-polyisoprene (SI diblock) copolymers having a wide range of compositions were synthesized via anionic polymerization, and the order-disorder transition temperatures (T ODT ) of the block copolymers were determined using dynamic viscoelastic measurements. We have shown that logarithmic plots of dynamic storage modulus (G') versus dynamic loss modulus (G) are very effective to determine the T ODT S of the block copolymers. The experimentally determined T ODT S are compared with the predictions made from currently held theories. We point out that the reliability of the predicted T ODT of a block copolymer depends, among many factors, on the accuracy of the expression for the Flory-Huggins interaction parameter X. We observed that the SI diblock copolymers having a low volume fraction of polystyrene or polyisoprene block (e.g., less than about 0.2) exhibited liquidlike rheological behavior at temperatures below their T ODT S, for instance at temperatures as low as about 30°C below the T ODT . We attribute this observation to the existence of defects in the long-range spatial order of microdomains (grain-boundary defects) which are continuous in three-dimensional space. Using the Onuki analysis that the extent of composition fluctuations of a block copolymer near the critical temperature, at a given temperature difference AT = T - T c from the critical temperature T c , is determined very much by the temperature dependence of the Flory-Huggins interaction parameter x, we have shown that the extent of composition fluctuations for SI diblock copolymers in the disordered state near the critical temperature is very small. Specifically, we have shown that for the same extent of composition fluctuations e, defined by e = 2 (1 - X/X c ), where X c is the value of X at the critical point, a temperature difference ΔT of 1°C for an SI diblock copolymer corresponds to ca. 20°C for a 1,2-polybutadiene-block-1,4-polybutadiene copolymer. This difference in AT between the two block copolymer systems is attributed to the difference in the temperature coefficient B appearing in the expression, X = A + B/T. Using the Onuki analysis, we have shown further that the extent of composition fluctuations in the disordered state near the critical temperature varies little with block copolymer composition.

156 citations



Journal ArticleDOI
01 Dec 1995-EPL
TL;DR: In this article, elastic and inelastic-neutron-scattering experiments were performed on a single crystal of the quasi-one-dimensional system CuGe0.993Si0.007O3.
Abstract: We have performed elastic- and inelastic-neutron-scattering experiments on a single crystal of the quasi-one-dimensional system CuGe0.993Si0.007O3. Our experimental data show unambiguously that both quasi-gapless antiferromagnetic fluctuations and gapped magnetic fluctuations, associated with a dimerized phase, coexist in this material below a spin-Peierls transition temperature TSP ≈ 9.2 K. When the temperature is lowered below TN ≈ 4 K, part of the system undergoes a new phase transition towards long-range antiferromagnetism, coexisting with the dimerized non-magnetic phase. We will describe the temperature and wave vector dependences of magnetic responses in these two phases, which can be understood as the superposition of two independent spectra.

149 citations


Journal ArticleDOI
TL;DR: In this article, Fourier transform infrared absorption spectroscopy has been performed on a GaN epitaxial film grown by the hydride vapor phase epitaxy on sapphire substrate.

140 citations


Journal ArticleDOI
TL;DR: In this article, conductivity and EMF measurements as a function of temperature and oxygen activity were used to find evidence for protonic conduction in Ba 2 In 2 O 5 material in moist atmospheres, especially at low temperatures.

Journal ArticleDOI
TL;DR: In this article, the double exchange mechanism was used to investigate the magnetoresistance properties of perovskite structures of metallic crystals of La 1-x Sr x CoO 3 (x = 0.20 and 0.30).
Abstract: Magnetotransport properties have been investigated for metallic crystals of La 1- x Sr x CoO 3 ( x =0.20 and 0.30) with perovskite structure. Around the ferromagnetic transition temperature ( T c ), fairly large negative magnetoresistance (MR) has been found. The magnitude of the MR is proportional to square of the magnetization above T c and appears to be enhanced as the metal-insulator compositional phase boundary is approached. The results are discussed in terms of the double exchange mechanism.

Journal ArticleDOI
TL;DR: In this paper, the relationship between the phase transition temperature x (0-0.026) and the window transition temperature τ c ( 0-67°C) in the most applicable range for advanced window coatings was clarified by formation of a single-phase film and precise determination of the amount of doping.
Abstract: Thin films of V1-x Wx O2 were deposited on glass and Si by dual-target sputtering and characterized by thin film X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS) and spectrophotometry. The relationship between x (0-0.026) and the phase transition temperature τ c (0-67° C) in the most applicable range for advanced window coatings was clarified by formation of a single-phase film and precise determination of the amount of doping. Tungsten doping linearly decreases τ c by 23° C/at.%W and also significantly reduces the thermal hysteresis loop width in optical transmittance.

Journal ArticleDOI
TL;DR: In this article, surface diffusion coefficients for hydrogen on the (100) face of nickel over a temperature range from 40 to 1000 K were calculated using local quadratic approximations to the potential and found that the surface diffusion process proceeds largely by a tunneling mechanism.
Abstract: We calculate surface-diffusion coefficients for hydrogen on the (100) face of nickel over a temperature range from 40 to 1000 K. The calculations include tunneling contributions from discrete-energy states. The results are in very good agreement with experiment. We find a dramatic leveling off of the Arrhenius plot at approximately 66 K, below which temperature the diffusion coefficient is virtually independent of temperature. The existence and magnitude of such a transition temperature agrees well with experimental findings and also with previous theoretical work based on path-integral transition-state theory. The present treatment provides insight into the origin of the effect. We evaluate the transition temperature analytically in terms of local quadratic approximations to the potential and find it to correspond approximately to the temperature at which the various low-energy bound-reactant states contribute equally to the diffusion coefficient. The nearly temperature-independent diffusion rate below the transition temperature corresponds to tunneling primarily from the ground state. The analytical expression for the transition temperature depends strongly on the magnitude of the frequency at the top of the potential barrier. We also demonstrate that this transition temperature does not correspond to a transition from over-barrier activated diffusion to tunneling diffusion, which has been previously proposed, and that the surface-diffusion process proceeds largely by a tunneling mechanism even well above the transition temperature.

Journal ArticleDOI
TL;DR: In this paper, the magnetization was obtained as a function of temperature and magnetic field of a Cu 1− x Zn x GeO 3 single-crystal with x ∼ 0.04.
Abstract: The magnetization was obtained as a function of temperature and magnetic field of a Cu 1− x Zn x GeO 3 single-crystal with x ∼ 0.04. The temperature dependence of the magnetic susceptibility in 0.1 T parallel to the c axis shows a clear cusp around 4.5 K and decreases rapidly below 4.5 K. There is no hysteresis between the data measured in zero-field-cooling and field-cooling processes. The field dependence of the magnetization parallel to the c axis at 2.0 K exhibits an apparent increase around 1.0 T, which corresponds to a spin-flop transition. The temperature and field dependences, the anisotropy, and the absence of the hysteresis undoubtedly prove the occurrence of an antiferromagnetic long-range order below 4.5 K instead of the spin-glass-like transition reported previously. Spins below the transition temperature are ordered almost parallel to the c axis. This is the first report of magnetic long-range order caused by nonmagnetic impurities.

Journal ArticleDOI
TL;DR: In this article, the authors have successfully fabricated ceramic superconductors of Hg-1223 with substitution of Pb for Hg, i.e. Hg1−xPbxBa2Ca2Cu3Oy, by using encapsulation and short time annealing techniques.
Abstract: We have successfully fabricated ceramic superconductors of Hg-1223 with substitution of Pb for Hg, i.e. Hg1−xPbxBa2Ca2Cu3Oy, by using encapsulation and short time annealing techniques. Samples fabricated in this manner may have nearly single phase structure and some enhancement of Tc can be achieved through this method. The materials of this ceramic with x ranging from 0 to 0.5 exhibit high-temperature superconductivity at temperatures falling in the range from 103 to 135 K. The sample with optimum doping of Pb of x = 0.34 and ° = 0.40 has a highest Tc of 135 K, and its diamagnetic onset temperature Tcdia = 143 K. The composition of this sample has been found experimentally and is specified by a formula of Hg0.66Pb0.34Ba2Ca1.98O8.4. The valence number for the copper constituent is given by V Cu = 2.30 . X-ray diffraction (XRD), transmission electron microscope (TEM) and electron probe microanalyzer (EPMA) analyses have been carried out for detailed investigation. Results indicate that the critical temperature for samples which were post-annealed with either oxygen flow or in high pressure of oxygen gas was increased, while that for those annealed in argon flow was decreased. Furthermore, the as-prepared samples were slightly in the under-doped state with respect to the vacancy. It was shown that Tc parabolically depends on the valence state of copper.

Journal ArticleDOI
TL;DR: In this article, the chemical inhomogeneity and stress induced by the difference of the unit cell volume between grain core and grain shell was investigated for BaTiO3-based ceramics sintered with additives.
Abstract: The dielectric temperature characteristics and microstructures of BaTiO3-based ceramics sintered with additives such as Sm2O3, CeO2, and Bi2O3:Nb2O5 were investigated using TEM, XRD, and EDS. For a Sm2O3-modified BaTiO3 ceramic whose additives were uniformly distributed in grains, the ferroelectric transition temperature (Tc) was shifted to a lower temperature, while the transition temperatures (T1 and T2) were shifted to a higher temperature. The additions of CeO2 and Bi2O3: PbO to BaTiO3 formed the chemical inhomogeneity which was composed of grain core, grain shell, and concentration gradient region. The dielectric curve versus temperature of CeO2-modified BaTiO3 has the shape of one strong peak, whereas BaTiO3 ceramics sintered with Bi2O3:Nb2O5 exhibit the broad dielectric constant at the low temperature region and 130 °C ferroelectric transition peak. The dielectric temperature characteristics of additives modified BaTiO3 were determined in terms of the chemical inhomogeneity and stress induced by the difference of the unit cell volume between grain core and grain shell.

Journal ArticleDOI
TL;DR: A semiconductor-metal transition occurring just below the Curie temperature was observed in single crystals of perovskite La1-xSrxMnO3 for x>or=0.175 as discussed by the authors.
Abstract: A semiconductor-metal transition occurring just below the Curie temperature TC was observed in single crystals of perovskite La1-xSrxMnO3 for x>or=0.175. For x or=0.13 whereas huge MR persists well below TC for the x=0.10 sample, which is probably due to a non-collinear spin configuration.

Journal ArticleDOI
TL;DR: In this paper, phase analysis and dielectric measurement have been conducted for a comprehensive study of the phase transition in the whole composition range of (1-x)Pb(Yb1/2Nb 1/2)O3-xPbTiO3 (PYN-PT) ceramic system.
Abstract: Phase analysis and dielectric measurement have been conducted for a comprehensive study of the phase transition in the whole composition range of (1-x)Pb(Yb1/2Nb1/2)O3-xPbTiO3 (PYN-PT) ceramic system. For all compositions, a continuous series of complete solid solutions of the antiferroelectric (AFE) and the ferroelectric (FE) compounds was found. With increasing PT concentration x, the phase transition in this system can be categorized as three distinct classes in connection with the degree of the structural ordering. The PYN-rich solutions showed a relatively sharp first-order paraelectric (PE)–AFE transition behavior and the transition temperature decreases rapidly with increasing x. For 0.10 < x < 0.25, the phase transition is broadened and frequency-dependent. Beyond x = 0.25, the normal PE–FE phase transition was observed and the transition temperature increases rapidly with increasing x. In the FE side, it was also revealed that the morphotropic phase boundary between pseudocubic and tetragonal structure lies in the vicinity of x = 0.5. Moreover, the resultant phase diagram with temperature and PT concentration is presented.

Journal ArticleDOI
TL;DR: In this article, the structural phase transition and ionic conductivity of 0.88ZrO2(0.12 − x)Sc2O3xAl2O 3 (0 ≤ x ≤ 0.005) was examined to clarify the mechanism of the cubic phase stabilization in this system.

Journal ArticleDOI
TL;DR: The BiO3 (BKBO) superconductor is cubic with a coherence length of 30-60 A. The basic properties of this compound are reviewed in this paper.
Abstract: Ba1−x K x BiO3(BKBO) has aT c (onset) of 34 K. It is the highest-temperature oxide superconductor which is cubic, with a coherence length of 30–60 A. The basic properties of this compound are reviewed.

Journal ArticleDOI
01 Jul 1995-Langmuir
TL;DR: In this article, the phase transition temperature of poly(N-isopropylacrylamide) (NIPA) gel was studied and the effects of surfactants having various chemical structures on the phase-transition temperature of NIPA gel were investigated.
Abstract: The effects of surfactants having various chemical structures on the phase transition of poly(N-isopropylacrylamide) (NIPA) gel have been studied. The phase transition temperature of NIPA gel, which is 34 °C in pure water, is elevated by several tens of degrees when a small amount of some surfactant is added to water. The transition temperature increases with surfactant concentration below the critical micelle concentration and is saturated at a certain temperature. The transition temperature strongly depends on the chemical structure in the hydrophilic part as well as the length of the hydrophobic portion of the surfactants. The transition temperature of the gel does not depend on the counterion species. These results imply that the effects of surfactants on the phase transition of the hydrophobic polymer gel may be utilized to quantitatively classify the interfacial behavior of surfactants in addition to the widely used hydrophile-lipophile balance (HLB).

Journal ArticleDOI
01 Jan 1995-Polymer
TL;DR: In this article, the viscoelastic properties of polypropylene fibres are investigated in a single-step stress relaxation test for small strains at temperatures between −50 and + 30 °C, thus well encompassing the glass transition temperature.

Journal ArticleDOI
TL;DR: In this paper, the phase transition at 754 K in sodium carbonate, Na2CO3, is characterized by the shear strain epsilon 5, with a coupled rotation of the carbonate groups.
Abstract: Detailed neutron powder diffraction data are presented which show that the phase transition (P63/mmc-C2/m) at 754 K in sodium carbonate, Na2CO3, is a second-order proper ferroelastic m=2 transition. The order parameter is characterized by the shear strain epsilon 5, with a coupled rotation of the carbonate groups. The diffraction peaks show clear evidence for the divergence of the temperature factors at the transition temperature due to the softening of the acoustic modes at small wave vectors. This results in the appearance of broad diffuse scattering at Bragg positions at the expense of the intensities of the Bragg peaks. We call this process 'lattice melting'.

Journal ArticleDOI
TL;DR: The magnetic ordering transition temperature in MnSi decreases with increasing pressure and tends towards absolute zero near 15 kbar as discussed by the authors. But as the critical pressure is approached, the crossover point is found to be near a minimum in the inverse susceptibility as a function of temperature.
Abstract: The magnetic ordering transition temperature in MnSi decreases with increasing pressure and tends towards absolute zero near 15 kbar. As the critical pressure is approached, we observe a crossover from a conventional transition of second order to one of weak first order. The crossover point is found to be near a minimum in the inverse susceptibility as a function of temperature. A qualitative description of this behaviour is given in terms of a temperature dependent renormalisation of the coefficients in a sixth order Landau expansion for the free energy.

Journal ArticleDOI
TL;DR: In this paper, the annealing effect on the structure and ferroelectric phase transitional behavior of vinylidene fluoride-trifluoroethylene (VDF-TrFE) copolymer with VDF 73 molar % has been investigated by the thermal analysis, X-ray diffraction and Fourier-transform Raman scattering measurements.
Abstract: The annealing effect on the structure and ferroelectric phase transitional behavior of vinylidene fluoride-trifluoroethylene (VDF-TrFE) copolymer with VDF 73 molar % has been investigated by the thermal analysis, X-ray diffraction and Fourier-transform Raman scattering measurements. Heat treatment of the sample in the temperature region below 125°C increases the transition temperature largely, which correlates intimately with an increment of the domain size along the chain axis and the growth of the all-trans chain stems in a crystallite. When the sample is annealed in the temperature region between the phase transitional point and the melting point, the X-ray coherent domain size decreases and the gauche-type disordered region increases within the domain, resulting in the decrement of the transition temperature.

Journal ArticleDOI
TL;DR: The La0.6Pb0.4MnO3 (LPMO) thin films were in situ deposited at different oxygen partial pressure and at a substrate temperature of 630 degrees C by pulsed laser deposition.
Abstract: The La0.6Pb0.4MnO3(LPMO) thin films were in situ deposited at different oxygen partial pressure and at a substrate temperature of 630 degrees C by pulsed laser deposition. The films grown at lower oxygen partial pressures showed an increase in lattice parameter and resistivity and a decrease in the insulator-metal transition temperature as compared to the stoichiometric LPMO thin film grown at 400 mTorr. Further, these oxygen-deficient thin films showed over 70% giant magnetoresistance (GMR) near the insulator-metal transition temperature against the 40% GMR in the case of stoichiometric thin films. (C) 1995 American Institute of Physics.

Journal ArticleDOI
TL;DR: In this article, the electrical resistance of the thiospinel CuIr 2 S 4 has been measured to clarify the pressure dependence of the metal-insulator transition temperature T M-I.

Journal ArticleDOI
TL;DR: In this article, the NdBa 2 Cu 3 O y (Nd123) bulk superconductor, to which Nd 4 Ba 2 Cu 2 O 10(Nd422) particles were intentionally added, was prepared through the so-called MMTG process in Ar (99% purity) flowing atmosphere at an ambient pressure.
Abstract: The NdBa 2 Cu 3 O y (Nd123) bulk superconductor, to which Nd 4 Ba 2 Cu 2 O 10 (Nd422) particles were intentionally added, was prepared through the so-called MMTG process in Ar (99% purity) flowing atmosphere at an ambient pressure. The quasi-single crystal thus grown was about 1 cm × 1 cm × 1 cm in dimension. It turned out that the Nd422 particles were uniformly distributed in the Nd123-phase matrix in a fashion similar to the distribution of the intentionally added Y211 particles in the Y123 phase matrix. The superconducting transition temperature T c for the sample subjected to post-annealing in oxygen atmosphere was 94 K. The critical current density J c was determined to be 45 000 A/cm 2 at 77 K and 1 T, when the field was applied parallel to the c -axis of the sample. To the best of our knowledge, the J c value is the highest and the size of the quasi-single crystal is the largest in the melt-textured Nd123 bulk superconductors so far reported.

Journal ArticleDOI
TL;DR: In this paper, two crystallization processes were observed separately in temperature; one in the range 218-225 K just above a glass transition region and the other above 227 K. It was concluded that the process proceeding around 220 K was probably the homogeneous-nucleation-based crystallization as found out in o -terphenyl, and that the decrease in the interfacial energy between crystal embryo and liquid must have played an important role for the crystallization to be observed macroscopically.