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Showing 1 to 19 of 19 for “"spin fluctuations"”.
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Spin fluctuations and high-temperature superconductivity in the copper oxides
The author reports studies of spin-fluctuation-induced superconductivity in the antiferromagnetically correlated copper oxide high temperature superconductors.
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Spin fluctuations and high temperature superconductivity in the copper oxides
The author reports studies of spin-fluctuation-induced superconductivity in the antiferromagnetically correlated copper oxide high temperature superconductors. The spin fluctuation mechanism is first studied within a weak coupling approximation. It is shown that the retarded interaction between …
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Pressure dependence of spin fluctuations in metallic glasses Zrâ â Niâ â ,Zrâ â (Nix/Feâ â â -x)â â and /Zrx/feâ â â -x
… modified McMillan equation which incorporates spin-fluctuations, the volume dependence of the spin fluctuation parameter, Asf, was determined in Zr75Ni25, ZrxFelOO-x , a11d Zr75(NixFelOO-x)25. It was found that with increasing pressure, spinfluctuations are suppressed at a faster rate in ZrxFe …
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Many-Body Effects in the Thermodynamic Properties of Fermi Liquids and the Electron-Phonon System and in the Excitation Spectrum of Liquid Helium-4
… I show that the T('3)lnT corrections due to spin fluctuations account for the finite temperature corrections to the leading term in the specific heat. I also calculate and compare the statistical and the dynamical quasiparticle spectra and show that differences between them partially account …
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Many-body effects in the thermodynamic properites of Fermi liquids and the electron-phonon system and in the excitation spectrum of liquid 4HE
… I show that the T3lnT corrections due to spin fluctuations account for the finite temperature corrections to the leading term in the specific heat. I also calculate and compare the statistical and the dynamical quasiparticle spectra and show that differences between them partially account …
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Angle-Resolved Photoemission Studies on the Many-Body Effects of High-Temperature Superconductor: Bi-2212
Spin fluctuations are defined as dynamic variations of spin density in both space and time. They are widely considered to play a essential role in the pairing mechanism of high temperature superconductors. Unconventional superconductors such as cuprates are believed to exhibit …
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Search, Discovery, Synthesis and Characterization of Itinerant Magnets Composed of Non-magnetic Constituents
… and magnetism, metamagnetic transitions, spin- and cluster-glass behavior, multisublattice magnetism, non-Fermi liquid behavior, and quantum criticality. Surprisingly, while many systems exhibit both local and itinerant magnetism, only two are known to contain no local moment ions: Sc3In …
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Light scattering studies of heavy fermion and high Tc superconductors
… of using light scattering techniques to probe spin fluctuations and crystal field excitations in metals. For example, light scattering from spin fluctuations in UBe13, UPt3, and URu2Si2 reveals a substantial q=O contribution to the magnetic susceptibility in these compounds. This result …
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Electrical noise study of spin glass dynamics in mesocopic CuMn
The electrical resistance of the archetypal spin glass CuMn is surprisingly sensitive to small changes in the spin configuration. This enhanced sensitivity results from long-range electron quantum interference at low temperatures. Due to this effect, substantial resistance noise is produced by …
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Electrical noise study of spin glass dynamics in mesoscopic copper manganese
The electrical resistance of the archetypal spin glass $\underline{\rm Cu}$Mn is surprisingly sensitive to small changes in the spin configuration. This enhanced sensitivity results from long-range electron quantum interference at low temperatures. Due to this effect, substantial resistance noise …
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Fluctuations and state preparation in quantum degenerate gases of sodium and lithium
… part of this thesis describes measurements of spin and density fluctuations in degenerate Fermi gases. We begin by presenting a proof-of-principle experiment that demonstrates how information about atomic fluctuations can be extracted from experimental images and used to measure the temperature …
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Photonic integration of electron-nuclear spin systems in semiconductor quantum dots
… interface of an electron and the nuclear spins within an optically active QD. Here we integrate the electron-nuclear spin system of a semiconductor QD into an open microcavity. We report progress on three fronts towards the generation of multidimensional photonic cluster states: First, we …
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Magnetic phases of large-spin ultracold bosons: quantum dimer models and spin liquid phases
… the plausibility of producing a quantum spin liquid (QSL) with ultracold bosonic atoms optically confined to the Mott insulating state. QSLs have received a great deal of attention for being an antiferromagnetic groundstate with many exotic properties, including the absence of local …
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Magnetic and Structural Instabilities in Cerium Diantimonides under Pressure
… stabilised by the presence of antiferromagnetic spin fluctuations at the quantum critical point. The magnetism in CeAgSb₂ can be tuned by hydrostatic pressure to a ferromagnetic quantum phase transition at pc ≃ 34 kbar. A closer study of electrical resistivity measurements around pc does resolve …
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Initialisation, control and readout of a nuclear-magnon quantum register
… of the system, since a single QD electron spin is coupled to approximately 100,000 nuclear spins. Combining these two elements, we have an isolated many-body nuclear ensemble interfaced to a central, proxy qubit, which we can interrogate optically. The system then plays host to a plethora …
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High-field SANS studies of the vortex lattice in YBCO
… by inelastic neutron scattering of the spin fluctuations at the metamagnetic field in Sr\(_3\)Ru\(_2\)O\(_7\) were shown. These important experiments have demonstrated the first microscopic evidence for a wholesale change in the character of the spin correlations at the metamagnetic …
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Inelastic light scattering studies of novel magnetodielectric mechanisms in transition metal CoCr2O4 and rare earth Ce2O3
DSpace SAF Submission Ingestion Package generated from Vireo submission #15784 on 2021-03-04 at 15:33:35
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Optical and core-level X-ray spectroscopy of correlated two-dimensional materials
… result in a helimagnetic ground state and spin-induced ferroelectric order, making bulk NiI₂ a type-II multiferroic. Using a combination of optical spectroscopic probes, including Raman, magneto-optics, and second harmonic generation, we demonstrate the persistence of multiferroic order to …
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Manipulating superconductivity in cuprates with selective ultrafast excitation
… appears to be due to competition with charge and spin stripe order. This study expands on a previous investigation that found that superconducting transport appears to be restored by selective excitation of a phonon mode that couples to the electronic charge order. The transient superconducting …