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Showing 1 to 14 of 14 for “"specific heat measurements"”.
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Resistivity and Specific-Heat Measurements Near Phase-Transitions in Metals
Made available in DSpace on 2015-05-12T22:38:59Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 7405697.PDF: 3230931 bytes, checksum: b73343b8693ce16b0fa8cb880c53a864 (MD5) Previous issue date: 1973
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Resistivity and specific heat measurements near phase transitions in metals
The ac calorimetry technique for measuring the specific heat has been modified to include a simultaneous measurement of the temperature derivative of the electrical resistivity on the same sample. Measurements are reported on f3-brass and gadolinium. The resistivity derivative of f3~brass is found …
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Neutron scattering and magnetization studies of the spin correlations on the kagomé lattice antiferromagnet KFe₃(Oh)₆(SO₄)₂
… with the Z2 symmetry. Depending on which measurements are performed, the critical behavior of the system can belong to either SO(2) or Z2 universality classes with two distinct critical temperatures; one is associated with the spontaneous breaking of the Z2 symmetry, and the other …
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Phonon Dispersion Relations in Chrystals
… the only experimental information came from specific heat measurements, and the success of the very much simpler Debye theory did not encourage development of the Born–von Karman crystal dynamics. However, discrepancies were apparent and some more detailed calculations were made (e.g. …
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Thermal conductivity of superconducting niobium
… from 0.31 K to above the transition temperature. Measurements were made on a single crystal cylindrical specimen for which R300/R ~ 200. The thermal 4.2:N conductivity in the superconducting state exhibited a maximum near 1.80 K. This maximum has been attributed to enhanced lattice conductivity as …
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Estudo da dupla Perovskita La2MnFeO6 preparada por reação de estado sólido
… (LFMO48) and 370.8 nm (LFMO96). According to the specific heat measurements, the LFMO’s have a ferrimagnetic phase transition at approximately 10 K, as data fit using the medium field theory. Peaks in the specific heat of the samples at higher temperatures were observed, occurring at different …
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Quantum oscillation studies in the unconventional superconductor YFe₂Ge₂ and in the Dirac semimetal candidates NbXSb (X = Ge/Si)
… masses have been measured. The context of these measurements with regards to the electronic structure in YFe₂Ge₂ has been discussed. It was found that the quasiparticle effective mass enhancement of the detected Fermi surface sheets can account for only ~40% of the mass enhancement previously …
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Elastic and inelastic X-ray scattering studies of the low dimensional spin-1/2 quantum magnet TiOCl
… scrutiny, there is an absence of direct measurements of the lattice dynamics associated with the transition. In this work we present an extensive study of a new one dimensional spin-Peierls compound, TiOC1. The magnetic susceptibility strongly indicates a singlet ground state, with two …
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Investigation of superconducting order parameters in heavy-fermion and low-dimensional metallic systems under pressure
… developed during this thesis and used for the measurements presented in Chapters 3 to 5. In Chapter 3 the possible realization of the inhomogeneous superconducting FFLO state in CeCoIn5 is studied by specific heat measurements under hydrostatic pressure, while in Chapter 4 the results of AC …
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Electronic and lattice vibrational properties of thorium hydrides
The low temperature heat capacities of several bulk samples of Th4H15 and Th4D15 have been measured in the normal state over the temperature range from 1.4 to 20 K. Values of the electronic heat capacity coefficient, y, and the Debye temperature, eD' have been determined. No isotope effect upon the …
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Neutron scattering and thermodynamic studies of quantum magnetism on the kagomé lattice
… to create a sample for neutron scattering measurements. Elastic neutron scattering measurements show the existence of long range magnetic ordering below T = 1.77 K. Integrated Bragg peak intensities were analyzed to determine the structure of ordered magnetic moments. Inelastic neutron …
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Thermodynamic and neutron scattering study of the spin- 1/2 kagome antiferromagnet ZnCu₃(OH)₆Cl₂ : a quantum spin liquid system
… model to the experiments on ZnCu₃(OH)₆Cl₂. Specific heat measurements down to dilution temperatures and under strong applied magnetic fields show a super linear temperature dependence with a finite linear term. Most importantly, we present neutron scattering measurements of the spin …
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Specific Heat and Thermodynamic Properties of Metallic Systems: Instrumentation and Analysis
… to study nano-particles and to facilitate specific heat measurements on samples where it is difficult to obtain enough material to run on the current large-scale adiabatic apparatus. This calorimeter is designed to measure sample sizes of less than 0.8 cc over a temperature range from 13 K …
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Unconventional Superconductivity in Uranium Ditelluride
… order parameter, based on polar Kerr effect and specific heat measurements. Subsequent work using cleaner samples failed to reproduce these results, attributing the discrepancies to inhomogeneities in early-generation crystals. One part of this dissertation focuses on providing a detailed and …