Physics & Atmospheric Science Faculty Research, Publications and Presentations: Recent submissions
Now showing items 261-280 of 532
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Analytical structure of the wave-number-dependent susceptibility of many-fermion systems at low temperature and long wavelength. II
For pt.I see ibid., vol.15, p.1523 (1977). It is shown that the nonanalytic structure of the wave-number-dependent susceptibility noted by Geldart and Rasolt is not removed by including repeated particle-particle scattering -
Temperature dependent resistivity in the low-resistance region for diffusive transport in two dimensions
The interpretation of the metal-insulator transition phenomena in disordered two-dimensional electron systems in terms of density-dependent scaling variables suggests the existence of a quantum critical point at some ... -
Quantum critical behavior in the insulating region of the two-dimensional metal-insulator transition
We show that the quantum critical point associated with the metal-insulator transition phenomenon in two dimensions controls an extended critical region encompassing not only the usual quantum critical sector but also a ... -
Density dependence of critical magnetic fields at the metal-insulator bifurcation in two dimensions
The density dependence of the critical in-plane magnetic field Bc at the bifurcation of the resistivity of two-dimensional electron systems with low levels of disorder is determined using the spin-polarization dependence ... -
Anisotropy of the critical magnetic susceptibility of gadolinium
The magnetic susceptibility along the c axis (xc) and in the basal plane (xb) has been measured on a single crystal of Gd in the reduced temperature range 410-4t1.310-2. Uniaxial anisotropy is observed. Magnetic dipole-dipole ... -
Surface-induced quantum density oscillations in the presence of an external magnetic field
The electron number density and spin density near the surface of a model metal, semimetal, or semiconductor are calculated in the presence of a uniform magnetic field. The magnetic field is applied in a direction perpendicular ... -
Dipole-dipole interactions and the critical resistivity of gadolinium
Results are presented for the electrical resistivity of a c-axis single crystal of high-purity gadolinium metal in the immediate vicinity of the Curie temperature. Numerical analysis reveals that the data are not well ... -
Effect of finite mean free path on spin-flip scattering rates near the critical point of magnetically ordered systems
The finite electron mean free path of conduction electrons is found to play an important role in determining spin-flip scattering rates, 1/sf, near a magnetic critical point. Small-momentum-transfer processes are suppressed ... -
Convergence properties as a function of spatial dimensionality of gradient expansions for the ground-state energy of an inhomogeneous electron gas
The extended Thomas-Fermi approximation for the ground-state energy of a many-fermion system is generalized to arbitrary spatial dimension. The authors' objective is a better understanding of convergence properties of such ... -
Short-distance expansion for the spin-spin correlation function of uniaxial dipolar systems
Motivated by recent work on the critical resistivity of gadolinium, a detailed study has been made of the temperature dependence of the two-point vertex function in the large-momentum regime. The operator-project expansion ... -
Influence of the envelope function on the ground-state energy of quasi-two-dimensional Wigner solids
At sufficiently low density, quasi-two-dimensional electron systems in their ground state form Wigner solids. In previous studies of the ground-state energy of such systems (in the absence of an applied magnetic field), ... -
Lattice sums for dipolar systems
A general method for the evaluation of lattice sums determining the effective parameters in the Hamiltonian of a dipolar magnetic system is described. The anisotropy of the Hamiltonian is examined for crystal structures ... -
Anharmonicity and cross section for absorption of radiation by water dimer
We calculate the absorption cross section of water dimer molecules in thermal equilibrium at temperatures typical of the lower atmosphere using quantum mechanical coupled nonlinear equations of motion. Empirical Morse-oscillator ... -
Negative electron-electron drag between narrow quantum Hall channels
Momentum transfer due to Coulomb interaction between two parallel, two-dimensional, narrow, and spatially separated layers, when a current Idrive is driven through one layer, is studied in the presence of a perpendicular ... -
Diamagnetic susceptibility of a dense electron gas
The authors calculate the diamagnetic susceptibility of a uniform interacting electron gas in the random-phase approximation. From this the exact high-density expansion of the diamagnetic susceptibility is obtained -
Motion of a point dipole in an infinite hole through a superconductor
The authors consider the system of a magnetic point dipole placed in an infinite square hole through a superconductor. Using the method of images they obtain the potential and the field distribution in the hollow. Using ... -
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Theory of impurity-concentration dependence of freezing temperatures of metallic spin glasses
The authors present a theory of the freezing temperature Tg of metallic spin glasses. Length scales associated with intrinsic sd scattering and finite temperature play essential roles. They describe an approach in which ... -
Plasmons in disordered, two-component, quasi-two-dimensional electron systems
The authors investigate the effect of elastic scattering of electrons on the properties of plasmons in a disordered, two-component, quasi-two-dimensional electron gas. Numerical results are given for dispersion relations ... -