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Related papers: Oxygen isotope effect on structural parameters and…

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Effect of oxygen off-stoichiometry on the structural and magnetic properties of La0.15Sr0.85MnO3-d (d = 0.02,0.14) has been studied employing low-temperature x-ray diffraction, calorimetry, electrical-transport and magnetization. The nearly…

Materials Science · Physics 2014-02-27 Aga Shahee , R. J. Chaudhari , R. Rawat , A. M. Awasthi , N. P. Lalla

Recent observations of the spectral line profiles and intensity ratio of the O VI 1032 {\AA} and 1037.6 {\AA} doublet by the Ultraviolet Coronagraph Spectrometer (UVCS) on the Solar and Heliospheric Observatory (SOHO), made in coronal holes…

Astrophysics · Physics 2009-10-30 Xing Li , Shadia Rifai Habbal , John Kohl , Giancarlo Noci

Oxygen isotope effects on the transport properties have been studied in high-quality epitaxial thin films of La_{0.75}Ca_{0.25}MnO_{3} and Nd_{0.7}Sr_{0.3}MnO_{3}. In the paramagnetic state, the resistivity can be well fitted by \rho (T) =…

Strongly Correlated Electrons · Physics 2007-05-23 G. M. Zhao , D. J. Kang , W. Prellier , M. Rajeswari , H. Keller , T. Venkatesan , R. L. Greene

We report the synthesis and characterization of a new electron-doped La-oxypnictide superconductor by partial substitution of lanthanum by thorium. The superconducting transition temperature at about 30.3 K was observed in La0.8Th0.2OFeAs…

Superconductivity · Physics 2009-11-13 J. Prakash , S. J. Singh , S. Patnaik , A. K. Ganguli

Intuitive entropic interpretations of the thermoelectric effect in metals predict an isotropic Seebeck coefficient at high temperatures in the incoherent regime even in anisotropic metals since entropy is not directional.…

Thermal expansion is a problem in many technological applications and its control represents a challenge in materials design. In this Letter, after studying the correlation between thermal expansion, cubic-to-rhombohedral transition and…

Materials Science · Physics 2018-09-13 Andrea Sanson

It has been recently predicted theoretically that due to nuclear motion light and heavy hydrogen molecules exposed to strong electric field should exhibit substantially different tunneling ionization rates (O.I. Tolstikhin, H.J. Worner and…

Atomic Physics · Physics 2016-08-24 X. Wang , H. Xu , A. Atia-Tul-Noor , B. T. Hu , D. Kielpinski , R. T. Sang , I. V. Litvinyuk

The currently available results of the isotope effect on the superconducting transition temperature T_c in Fe-based high-temperature superconductors (HTS) are highly controversial. The values of the Fe isotope effect (Fe-IE) exponent…

Superconductivity · Physics 2015-05-19 R. Khasanov , M. Bendele , A. Bussmann-Holder , H. Keller

Ice Ih has been studied by path-integral molecular dynamics simulations, using the effective q-TIP4P/F potential model for flexible water. This has allowed us to analyze finite-temperature quantum effects in this solid phase from 25 to 300…

Materials Science · Physics 2011-08-22 Carlos P. Herrero , Rafael Ramirez

The mobility of O atoms at very low temperatures is not generally taken into account, despite O diffusion would add to a series of processes leading to the observed rich molecular diversity in space. We present a study of the mobility and…

Astrophysics of Galaxies · Physics 2014-02-11 M. Minissale , E. Congiu , F. Dulieu

Effective collision strengths for forbidden transitions among the 5 energetically lowest finestructure levels of O II are calculated in the Breit-Pauli approximation using the R-matrix method. Results are presented for the electron…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 R. Kisielius , P. J. Storey , G. J. Ferland , F. P. Keenan

Thermoelectric properties of the system La$_2$NiO$_{4+\delta}$ have been recently discussed [Phys. Rev. B 86, 165114 (2012)] via ab initio calculations. An optimum hole-doping value was obtained with reasonable thermopower and…

Strongly Correlated Electrons · Physics 2016-04-25 Victor Pardo , Antia S. Botana , Daniel Baldomir

La$_2$NiO$_{4+\delta}$ has attracted increasing interest in recent years, both as oxygen electrode in solid oxide fuel cells and electrolysers due to its high electrochemical activity at intermediate to high temperatures, and as key…

Materials Science · Physics 2025-07-03 Adeel Riaz , Alexander Stangl , Mónica Burriel , Michel Mermoux

We report anisotropic thermal expansion of the parent, AEFe2As2 (AE = Ba, Sr, and Ca), compounds. Above the structural/antiferromagnetic phase transition anisotropy of the thermal expansion coefficients is observed, with the coefficient…

Materials Science · Physics 2015-05-13 Sergey L. Bud'ko , Ni Ni , Paul C. Canfield

We systematically investigate effect of oxygen isotope in $(Pr_{1-x}Sm_x)_{0.7}Ca_{0.3}CoO_3$ which shows a crossover with x from ferromagnetic metal to the insulator with spin-state transition. A striking feature is that effect of oxygen…

Strongly Correlated Electrons · Physics 2009-11-11 G. Y. Wang , X. H. Chen , T. Wu , G. Wu , X. G. Luo , C. H. Wang

We investigate the temperature-pressure phase diagram of BaTiO_3 using a first-principles effective-Hamiltonian approach. We find that the zero-point motion of the ions affects the form of the phase diagram dramatically. Specifically, when…

Materials Science · Physics 2009-12-17 Jorge Iniguez , D. Vanderbilt

The unusual non-linear effects in hopping conduction of single-crystal La_{2}CuO_{4 + \delta} with excess oxygen has been observed. The resistance is measured as a function of applied voltage U (10^{-3} V - 25 V) in the temperature range 5…

Superconductivity · Physics 2009-10-31 B. I. Belevtsev , N. V. Dalakova , A. S. Panfilov

We calculated reaction rate constants including atom tunneling of the reaction of dihydrogen with the hydroxy radical down to a temperature of 50 K. Instanton theory and canonical variational theory with microcanonical optimized…

Chemical Physics · Physics 2016-05-31 Jan Meisner , Johannes Kästner

The phenomenon of negative thermal expansion (NTE) deals with the increase of the lattice parameters and the volume of the unit cell when the material is thermally cooled. The NTE is typically associated with thermal phonons and anomalous…

Strongly Correlated Electrons · Physics 2023-03-10 Wojciech Brzezicki , Filomena Forte , Canio Noce , Mario Cuoco , Andrzej M. Oleś

Although the isotope effect in superconducting materials is well-documented, changes in the magnetic properties of antiferromagnets due to isotopic substitution are seldom discussed and remain poorly understood. This is perhaps surprising…